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Full text of "Programme of studies for the high school"


CURRGDHT 




Ex LIBRIS 

UNIVERSITATIS 

ALBERT/ENSIS 






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20< 




Programme of Studies 
For the High School 



Bulletin B 



Guide for Practical and Experimental Work 



in 



CHEMISTRY 2, PHYSICS 2 
and BIOLOGY 2 



Additional copies of this Bulletin may be had from 

the General Office of the Department of Education 

at 20 cents the copy. 

Edmonton: Printed by A. SHNITKA, King's Printer 
1944 



onrvERsmr libraw 

UNIVERSITY OF ALBERTA 



CHEMISTRY 2 



TEXTBOOK: New^World of Chemistry: Jaffe (Silver Burdett Co.) 

FOR TEACHERS' AND STUDENTS' REFERENCE: Laboratory and 
Workbook Units in Chemistry, to accompany the textbook. 

N.B. — This workbook is available from the School-Book Branch; but students 
are not required to provide themselves with copies of it. 

Foreword 

" Laboratory work" in Chemistry 2 is not a course in itself, separate and 
distinct from a course in " theory, " but is merely part of the procedure for 
teaching the theory. It is not designed to produce research students, but rather 
to illuminate the facts and theory of the subject, and provide, along with other 
activities, some meaningful experience for the student that may facilitate his 
comprehension. Teaching and practical work must therefore go hand in hand, 
and be kept in step. Failure to synchronize theory and practical work defeats 
the purpose of the course. Students who memorize the theory without having 
had the benefit of practical exercises cannot meet the requirements of the course ; 
but, on the other hand, there can be little justification for a procedure that 
permits the practical work to outrun the theory, or that concentrates the practical 
work in a few weeks at the end of the term. ^3 

The Outline for Practical Work, which follows, is suggestive rather than 
prescriptive. More exercises may be required to meet the needs of a particular 
class; and other and better exercises may be devised by the teacher in con- 
sultation with his students. The suggested outline will, however, save some of 
the teachers' and students' time. 

The foregoing statement will serve to explain the following regulation with 
respect to " laboratory work": 

" Instructors in Chemistry 2 are no longer required to submit to the 
Examinations Branch of the Department at the end of the year a special report 
on the laboratory work of their students." 

CLASSROOM LIBRARY 

Every classroom for Chemistry 2 should be provided with a library of 
reference books for the use of teacher and students. A suitable list of such 
books may be found in the High School Regulations for the Year Ending 
July 31, 1944; and these books may be had from the School-Book Branch. 

DIRECTIONS TO STUDENTS 

1. Before coming into the laboratory to perform an experiment, study the 
directions outlined here in the procedure. Be sure that you understand 
what you will be doing, and why. Do not attempt an experiment the 
relevant theory of which you have not a lready studied. 

2. Question each step as you proceed. Learn the names of the chemicals 
and apparatus. Examine materials used; and also the precipitates formed, 
and other products, so as to be able to identify them as your work pro- 
gresses. 

3. Follow your directions closely and use great care when flames, acids, and 
bases, and inflammable liquids are employed. 



4. Use small quantities of chemicals. Larger quantities frequently ret aid 
the progress of the experiment. 

5. Record all results of your experiment and make liberal use of diagrams 
(sectional) in making your report. These diagrams should be neatly drawn 
and neatly labelled. 

6. Be sure your apparatus is clean. After completion of the experiment, 
clean all apparatus and leave the desk in a dry and tidy condition. 

7. Learn the capacity (in cc.) of an ordinary test tube so as to be able to measure 
out approximate volumes (10 cc.) without loss of time. 

8. In case of accident, call your instructor at once. 

In the following exercises — 

" Result?" means to make a written record of your observation. 
Interpret "Odor?" " Equation?" also in written form. 
Unless the word " dilute" is used before an acid, the concentrated acid is 
to be used. 

Bracketed numbers refer to related material in the authorized textbook. 

LIST OF EQUIPMENT: CHEMISTRY 2 

This List makes adequate provision for practical work. At the present 
time, however, it may be difficult to get some of the apparatus and materials 
listed; and it may be necessary for instructors to improvise equipment and 
substitute other materials. 

SUPPLIES FOR SIX STUDENTS 

The following is a list of the supplies needed for six students working in 
three groups of two each or for three students working singly. A reasonable 
margin has been allowed for breakages. It includes several pieces of equipment 
which are also required for Chemistry 1. The list is divided under sub-headings 
as follows: 

A. — Apparatus required for all groups. It is desirable that this be issued 
at the beginning of the year, especially if drawers and cupboards 
lock. 

B. — (1) Apparatus for common use of several groups. This should be 
considered a minimum list. 

(2) Additional and more extensive apparatus which should be in- 
cluded for large classes or even for small ones if circumstances 
permit. 

C. —Chemicals. 

D. — Materials which may be obtained locally. 



A. — Apparatus required for all groups. (Quantities are sufficient for 
three groups.) 

Note: "Pyrex" or some good resistance glass is recommended for all glassware. 
Although it is more expensive, it is so much more durable that its use results in 
greater economy being effected. 



Description Quantity 

Alcohol lamps, 4 oz. at least (or bunsen burners with the fish tail 

attachments if gas is available) 3 

Beakers, low form with lip, 250 cc 6 

Beakers, low form with lip, 150 cc... 6 

Blowpipes, 8-10 inches, brass recommended 3 

Blue Glasses, 2" x 1" 3 

Bottles for collection of gases, etc., at least 8 oz., low form 12 

Bottles for reagents, glass stoppers, at least 4 oz 30 

Burettes, 50 cc, Mohr type for pinchcock recommended 3 

Burette, fittings for above, burette tip with rubber tubing and 

pinchcock 3 

Filter papers, 5" in dia., coarse for rapid work 1 pkg. 

Flasks, Erlenmeyer, 300 cc, No. 6 top 4 

Rubber stoppers, two holes, No. 6 for the above flasks 4 

Funnels, glass, 65 mm. dia., 150 mm. stem 3 

Glass tubing, 6 mm., ext. dia 1/8 lb. 

Graduates, 100 cc to show 1 cc 3 

Graduates, 10 cc 3 

Non-combustible rods for flame tests (or see B list) . 3 

Pipettes, 10 cc, (Note: 3 burettes may be used instead) 1 

Pneumatic troughs, galvanized iron or glass, about 7"xl0"x5".. 3 

Retorts, 125 to 250 cc, glass for making bromine 3 

Retort stands, base, about V/j 1 x Q}4" . 3 

Retort stands, rings — large, 334" di&- inside; small, 2^ /r dia 3 each. 

Retort stands, fixtures, burette clamp 3 

Rubber tubing, 3/16" dia. inside for generators and connections.. 8 ft. 

Test Tubes, 16 mm. dia. outside, 150 mm. long 30 

Test Tubes, 20 mm. dia. outside, 150 mm. long (prep, of 2 ) 5 

Rubber stoppers, 1 hole, size No. 2, large end, 20 mm 3 

Test Tube brush, bristle end..... 3 

Test Tube racks, large enough to hold 10 tubes upright rec 3 

Thistle tube, stem, 6 mm. dia. outside ._ 4 

Tubes, combustion, dia, inside, about 15 mm., length, 5-12" 3 

Wire gauze squares, iron or copper, 4" side 3 



B. — (1) Apparatus for the common use of several groups. 

Description Quantity 

Balance, with weights, capacity, 100 to 150 grams, sensitivity, 5 mg. 
(Note: If balance is to be used for Physics 2 as well, one of greater 

capacity 7 should be obtained). 1 

Bottles, regent, glass stoppers, 500 cc capacity 10 

Beaker, low form with lip, pyrex, capacity, 600 cc 1 

Barometer, graduated in Metric scale, aneroid is recommended .... 1 

Files, triangular, 5" 3 

Funnel, glass, dia. at least 80-100 mm 1 

Mortar and pestle, about 5 inches in dia 1 

Thermometer, Centigrade, range, —10° — 110°, solid stem..... 1 

Platinum wire, lengths 3" long sealed in glass tubing 6 in. 

Flask, Erlenmeyer, 500 cc. with generator fittings if Kipp's Apparatus 

is not available (See below) 1 

Furniture: (1) Tables for students' practical work in the laboratory. Sug- 
gestions re. construction: height, 36 inches; width, 4 ft.; length, depends 
on requirements and space available. Each group needs a space about 
four feet wide and half the width of the table: this gives about eight square 



6 

feet. A shelf along the centre of the table is convenient for reagent bottles. 
Drawer and cupboard space for storing apparatus in students' tables is 
needed and should be added when finances will permit. If they are con- 
structed with locks, groups may be given sets of apparatus at the beginning 
of the year and held responsible for it throughout the year. (2) Cupboards, 
which will lock, are needed for storing chemicals and apparatus. (3) Demon- 
stration table for instructor, specifications, see above, width 2J/£ to 4 ft. 

B. — (2) Additional and more extensive apparatus which should be included 
for large classes. 

Kipp's gas generator, capacity of generating chamber, 500 cc 1 

Fume cupboard: As poisonous gases are very injurious for students and 
teacher, a fume cupboard for the preparation of such gases should be 
provided. Position, near demonstration table in the classroom so that 
it may be used conveniently during instruction periods, as well as during 
laboratory periods. 

Size, at least two feet square; bottom of cupboard, 3 feet from floor; height, 
about 3}/2 feet, that is, top, 63^ feet from floor. 

Ventilation: If poisonous gases are to be prevented from entering the room, 
this cupboard should be connected to the outside of the building by means 
of a pipe. If it is not feasible to do this through the heating or ventilating 
systems of the building, an electric fan may be found to be effective. 

NOTE: Large classes will require additional quantities of the apparatus listed 
under B (1) above. 

C. — Chemicals. (For class of six, i.e., three groups.) 

NOTE: Even for classes as small as six, it will be found to be more economical 
to buy in larger quantities than those given below. 

Description Quantity 

Alcohol, Methyl, (wood spirits) _. 1 pt. 

Alcohol, denatured 28 gm. 

Alum, pure powder 60 gm. 

Aluminium foil or turnings 7 gm. 

Aluminium Chloride C.P 7 gm. 

Aluminium Nitrate C.P 7 gm. 

Aluminium Sulphate C.P 14 gm. 

Amonium Carbonate C.P.... 7 gm. 

Ammonium Chloride C.P..... 120 gm. 

Ammonium Hydroxide C.P 500 gm. 

Ammonium Nitrate C.P... 7 gm. 

Ammonium Molydate C.P 14 gm. 

Ammonium Sulphate C.P 7 gm. 

Ammonium Sulphide Solution 56 gm. 

Ammonium Sulphite C.P 7 gm. 

Ammonium Phosphate C.P.... .'— - 7 gm. 

Ammonium Thiocyanate C.P 14 gm. 

Arsenious Oxide (Demon, only) 7 gm. 

Barium Chloride C.P 14 gm. 

Barium Nitrate C.P 14 gm. 

Bismuth Trichloride 7 gm. 

Bleaching Powder 28 gm. 

Borax, crystals 14 gm. 

Calcium Carbonate, ppt 28 gm. 

Calcium Carbonate, marble chips 1/8 lb. 



Description Quantity 

Calcium Chloride, C.P. . - - -- 28 gm. 

Calcium Hydroxide, Tech .. 60 gm. 

Calcium Nitrate C.P.. - — — 7 gm. 

Carbondisulphide - - 7 gm. 

Carbontetrachloride - 7 gm. 

Charcoal, animal, powder 28 gm. 

Charcoal, lumps or blocks.. — 28 gm. 

Chloroform, Tech 14 gm. 

Cobalt Nitrate 7 gm. 

Copper filings - 57 gm. 

Cupric Bromide — - - 28 gm. 

Cupric Nitrate C.P - 14 gm. 

Cupric Sulphate, C.P., pow.... 14 gm. 

Cupric Sulphate, Tech. 28 gm. 

Cupric Chloride, C.P 7 gm. 

Ferric Chloride. C.P— - — 57 gm. 

Ferric Nitrate, C.P. 7 gm. 

Ferric Sulphate, C.P. 7 gm. 

Ferrous Chloride, C.P. .'. 7 gm. 

Ferrous Sulphide, granular... 114 gm. 

Glucose, pure anhydrous 56 gm. 

Hydrochloric Acid, C.P 1.5 lb. 

Iron filings 28 gm. 

Lead Nitrate, C.P....... -~ - - -- 114 gm. 

Lead Peroxide, Tech 28 gm. 

Lead Oxide (litharge) 28 gm. 

Lead Oxide (red lead) 42 gm. 

Lithium Chloride , 7 gm. 

Litmus, Best qual., gran 14 gm. 

Litmus paper, blue, vial of 100 strips 1 vial 

Litmus paper, red 1 vial 

Magnesium ribbon .. 4 gm 

Magnesium Carbonate, heavy 28 gm 

Magbesium Chloride, C.P : 7 gm 

Magnesium Nitrate, C.P 7 gm 

Magnesium Sulphate, C.P 114 gm 

Manganese Dioxide, C.P. 28 gm 

Manganese Dioxide, Tech. . 63 gm 

Mercury metal 5 gm 

Mercuric Chloride, C.P 28 gm 

Mercuric Nitrate, C.P 7 gm 

Mercurous Nitrate, C.P... 14 gm 

Methyl Orange....! 7 gm 

Nitric Acid, C.P 1.5 lb 

Nickel Chloride 7 gm 

Phenolphthalein 7 gm 

Portland Cement 14 gm 

Potassium Bromide, C.C. or U.S.P 35 gm 

Potassium Carbonate, C.P 7 gm 

Potassium Chlorate, C.P,, pow 14 gm 

Potassium Chloride, C.P 28 gm 

Potassium Chromate, C.P 57 gm 

Potassium Ferricyanide, C.P... 28 gm 

Potassium Ferrocyanide, C.P , 28 gm 

Potassium Iodide 35 gm 

Potassium Nitrate, C.P 21 gm 



Description Quantity 

Potassium Phosphate, C.P 7 gm 

Potassium Sulphate, C.P.... 7 gm 

Potassium Sulphite, C.P 7 gm 

Silver Nitrate... 35 gm 

Sodium Bicarbonate, C.P 35 gm 

Sodium Carbonate, Tech., pow... _ 84 gm 

Sodium Chloride, C.P 14 gm 

Sodium Hydroxide, C.C. sticks. 114 gm 

Sodium Nitrate, C.P., pow 28 gm 

Sodium Peroxide, pow 7 gm 

Sodium (Disodium) Phosphate, C.P 57 gm 

Sodium Sulphate, C.P 7 gm 

Sodium Sulphite, C.P 7 gm 

Sodium Sulphide, C.P 7 gm 

Sodium Thiosulphate 14 gm 

Starch, corn 114 gm 

Strontium Chloride, C.P 14 gm 

Sulphuric Acid, C.P 1 lb. 

Zinc, C.P. (low in As.), gran 57 gm 

Zinc Chloride, C.P 7 gm 

Zinc Nitrate, C.P s 7 gm 

Zinc Sulphate, C.P. ... 28 gm 

Zinc Sulphide, Tech 14 gm 

NOTE: The above list includes small quantities of a variety of salts which 
may be used as " unknowns" in Exercises 51 and 52. 
Equivalents: 28.3 grams = 1 oz.; 1 pound =453.6 grams. 

D. — Materials which may be obtained locally. (For class of six, three groups.) 

Candles, paraffin, for demonstration 2 

Clay, well pulverized l i lb. 

Clock spring, 1/8" wide... .. 1 ft. 

Copper sheet, medium gauge, 17 sq. in. cut into strips about 

3" x 3/8". 
Zinc sheet or new galvanized iron, same as above. 

Distilled water l 2 gal. 

Finger bandaging, 2" wide - 1 yd. 

Glass (window) cut in 3" squares 6 squares 

Honey 1 oz. 

Iron nails, bright, 1^-2" 6 

Lime (quicklime) 1 lb. 

Molasses, black 2 oz. 

Red calico 1 '8 yd. 

Sugar, cane or beet 28 gm. 

Wooden splints— 6"-8" long. ... 2 doz. 

Oatmeal 1 oz. 

Vegetable oil (olive, peanut, etc.) 1 oz. 

Vinegar . 1 oz. 



OUTLINE FOR PRACTICAL 

WORK 

N.B. — References are made to chapters and pages of the Textbook. 

1. BROMINE AND IODINE 

(Chapter 10) 

Bromine and iodine may be prepared by the students (p. 159), but it is 
suggested that these and chlorine water (p. 150) be prepared in advance by the 
teacher. Sodium salts may be substituted for potassium salts in this exercise. 

Apparatus — Test tubes and rack. Burner. 

Materials — Potassium chloride. Potassium bromide. Potassium iodide. 
Chlorine water. Bromine water. Silver nitrate solution. Ammonium hydrox- 
ide. Sulphuric acid (1 of acid to 2 of water). Manganese dioxide. Carbon 
disulphide or carbon tetrachloride. Alcohol. Iodine crystals. Starch. Tincture 
of iodine. 

Tests for a chloride, a bromide and an iodide. 

1. To a concentrated solution of each of (1) potassium bromide, (2) 
potassium iodide, in separate test tubes, add a few cc. of chlorine water (p. 162). 
Colours? Equations? 

2. Half fill three test tubes with a dilute solution of a chloride, a bromide 
and an iodide, respectively. To each add a few drops of silver nitrate solution 
(p. 156). Colours? Equations? 

3. After allowing the precipitate formed in (2) to settle, pour off the super- 
natent liquid. To each precipitate add about 5 cc. of ammonium hydroxide. 
Shake. Result? 

4. Prepare a precipitate of silver chloride and let stand for a few minutes 
in a strong light. Result? 

5. Into each of three test tubes pour about Yi cc. of sulphuric acid. (If 
not previously prepared by the teacher, this acid, can be prepared by adding, 
slowly and carefully, 1 part of sulphuric acid to 2 parts of water). Into the 
first test tube pour about Yi cc. of a mixture of potassium chloride and man- 
ganese dioxide. To the second add a similar amount of a mixture of potassium 
bromide and manganese .dioxide, and to the third add a mixture of potassium 
iodide and manganese dioxide. Warm each test tube gently if no reaction is 
visible (p. 159). Colours? Equations? 

Solubility of halides. 

6. Dissolve a pinch of (1) potassium bromide in 5 cc. of water, and of (2) 
potassium iodide in 5 cc. of water. To each add about 2 cc. of carbon disul- 
phide or carbon tetrachloride. Shake and allow to stand. Now to each test 
tube add a little chlorine water and shake. Again allow to stand (p. 162). 
Result? Equations? 

7. Into four test tubes put about 2 cc. of water, alcohol, carbon disulphide, 
potassium iodide solution, respectively. Drop a small crystal of iodine in 
each and shake (p. 162). Tabulate the colours and solubilities. 



10 



Test for iodine. 

8. (a) To a solution of starch (obtained by boiling, if necessary,) add a 
few drops of tincture of iodine. Result? 

(b) To a solution of potassium iodide add a little tincture of iodine. 
Result? Now add to this solution chlorine water. Result? 

9. Put a small crystal of iodine in a test tube. Heat. Result? 

2. HYDROCHLORIC ACID 

(Chapter 13) 

Apparatus — Test tubes and rack. Beaker. Stirring rod. Burner. 
White Paper. 

Material— Hydrochloric acid. Sodium hydroxide. A second acid. A 
second base. Litmus. Phenolphthalein. Methyl orange. Sulphuric acid. 
Potassium chloride. 

1. Action of Indicators. 

Half fill each of six test tubes with water. Number 1 to 6. To numbers 
1, 3 and 5 add a few drops of dilute hydrochloric acid, and to numbers 2, 4 and 
6 pour a few drops of sodium hydroxide solution. Into 1 and 2 pour a few 
drops of litmus solution, into 3 and 4 a little phenolpthalein, and into 5 and 6 
methyl orange. Repeat the experiment using a different acid and base (p. 218). 
Tabulate your results, as indicated below: 





Colour of 
Litmus 


Colour of 
Phenolphthalein 


Colour of 
Methyl Orange 


Hydrochloric Acid 




Second acid 








Sodium hydroxide 








Second ba^e 









2. Neutralization. 

Into a beaker half full of water, add about 3 cc. of dilute sodium hydroxide 
solution. Add several drops of phenolphthalein. Stir. Place a sheet of white 
paper under the beaker. Now add slowly, while stirring, dilute hydrochloric 
acid till the colour just disappears. On the addition of a single drop of base the 
colour should begin to reappear. Explain. Equation? (See page 218.) 

3. Test for hydrogen chloride. 

Pour Yi cc. of concentrated sulphuric acid into a test tube and add a large 
pinch of potassium chloride. Warm gently and breath across the top of the 
tube. Result? (See page 221.) 

(The fumes observed are due to the condensation of moisture in the breath, 
as it dissolves in the gas generated.) 

4. Solubility of hydrogen chloride gas. 

Put about 1 cc. of hydrochloric acid into a test tube fitted with a one- 
hole stopper in which is a piece of glass tubing about 3 inches long, open at 
both ends. Boil the acid till, on breathing over the end of the tubing, white 



11 

fumes appear. Invert the test tube and quickly immerse the tubing in a beaker 
of water. Result? 

3. SODIUM HYDROXIDE 

(Chapter 14) 

Apparatus — Test tubes and rack. Delivery tube. Collecting trough. 

Materials — Caustic soda (sticks or pellets). Copper sulphate. Ferric 
chloride. Lead nitrate. Ferrous sulphate. Aluminum sulphate. Chalk or 
limestone. Ammonium chloride. 

1. Properties. 

Observe a small piece (M inch of stick) of caustic soda. (Do not handle.) 
Allow it to remain exposed to moist air for a few moments. Result? Drop the 
piece in about 2 cc. of water in a test tube. Note any change in temperature as 
it dissolves. Now dilute the solution with about 15 cc. of water. Rub a little 
of this solution between the finger and thumb. (Feel?) (See page 226.) 

2. Precipitating reagent. 

Into separate test tubes, pour about 10 cc. of each of the following solutions: 
copper sulphate, ferric chloride, lead nitrate, ferrous sulphate, aluminum sul- 
phate. To each solution add a few drops of the solution prepared in (1). Re- 
sults? Equations? 

Now add 2 or 3 cc. of the basic solution to each of the test tubes. Results? 

3. Reaction with an anhydride. 

Prepare a test tube of pure carbondioxide. Invert it in a concentrated 
solution of caustic soda in a beaker, and allow to stand. Agitate a little if 
necessary to speed up reaction. Result? Equation? (See page 229.) 

4. Test for ammonium radical. 

Into a test tube place a pinch of ammonium chloride (or other ammonium 
salt). Add about 1 cc. of caustic soda solution and warm. Odor? Equation? 

Repeat this experiment but use a few cc. of a solution of an ammonium 
salt instead of the solid as above. Result? 

4. NEUTRALIZATION 

(Chapter 14) 

Apparatus — 2 Burettes (50 cc). Clamp. Stand. Beaker. Stirring 
rod. 

Materials— Hydrochloric acid (1 of acid to 100 of water). Sodium 
hydroxide solution (1/10 Molar). Phenolphthalein. 

1. Titration. 

Set up two clean burettes (preferably 50 cc.) fitted with clamp or tap, 
on a stand. Fill burette A with hydrochloric acid (previously prepared by the 
teacher — 1 of acid to 100 of water). Fill burette B with approximately .1 
( = 1/10) molar sodium hydroxide solution (previously prepared by the teacher). 
Run a little acid and base out of each burette into a beaker. Discard this 
liquid. Now make careful readings of the amount of acid and base in the burettes, 
by observing the position of the bottom of the meniscus, read at eye level. 
Record these readings. 



12 

Into the beaker run about 20 cc. of the acid. Add several drops of phenol- 
phthalein solution. Keep a sheet of white paper under the beaker to aid in 
detecting color changes. Place the beaker under burette B and run out about 
10 cc. of the basic solution, stirring constantly. Continue to add the basic 
solution, drop by drop, stirring carefully. When the addition of a single drop 
of sodium hydroxide will produce a permanent pink color, which disappears 
by the addition of a drop of the acid, the neutralization is complete. This 
titration is said to have reached the "end point". 

Take the readings from the burettes. Calculate the volume of each solu- 
tion used. Assuming the basic solution to be 1 normal (or 1 molar), calculate 
the weight of hydrogen chloride in 1 liter of solution used. Calculate 
also to 2 decimal places the normality of the acid solution, using the formula 

Va X Na = Vb X Nb 

when V = volume 

N = normality 
A = acid 
B = base 

(Va would read "Volume of acid".) 



5. IONIZATION 

(Chapter 16) 
Apparatus — Glass plate. Test tubes and rack. 
Materials — Tartaric or oxalic acid. Slaked lime. Litmus. Several 



salts. 

1. Effect of moisture on acid and basic reactions. 

Place a clean, dry glass plate on a sheet of white paper. On the plate 
place separately a pinch of dry tartartic or oxalic acid, and a little slaked lime. 
Test the acid and lime with separate pieces of dry red and blue litmus. Result? 

Now moisten each of these substances with a drop or two of water. Again 
test with the litmus papers. Results? Explanation? 

2. Effect of dilution upon ionization. 

Into each of 3 dry test tubes put a small quantity (about 1 cc.) of copper 
sulphate (powdered), copper chloride and copper bromide, respectively. In 
this exercise observe carefully for colour changes. To each test tube add one 
or two drops of water, then slowly add more water till no further colour change 
occurs. The final colour should be a light blue. Tabulate your results in the 
following form: 



Salt- 


Formula 


COLOUR WHEN 


Dry 


Moist 


Concen- 
trated 
solution 


Dilute 
solution 


Copper sulphate 










Copper chloride 












Copper bromide 













Write equations indicating the ionization. 



13 



3. Reversible reaction. 

To a solution of sodium carbonate in a test tube, add some potassium 
nitrate solution. Result? Explain. Equation? 

Into a beaker put about 1 grain of bismuth trichloride. Add a drop or two 
of hydrochloric acid. If necessary add a little more, just enough to dissolve 
the salt. Now add water slowly, stirring constantly till a definite change 
occurs. Result? The equation for the reaction is 
BiCl 3 + H 2 BiOCl + 2 HC1. 

The bismuth oxychloride is insoluble. 

Now add dilute hydrochloric acid till the reaction is completely reversed. 

6. HYDROLYSIS 

(Chapter 16) 

Apparatus — Test tubes and racks. 

Materials — Litmus. Several salts. 

1. Litmus reactions on solutions of salts. 

Into separate test tubes put a pinch of each of the following salts: sodium 
chloride, ferric chloride, copper sulphate, potassium nitrate, sodium carbonate, 
ammonium sulphate, sodium borate (borax). To each test tube add about 
5 cc. of water and shake. Drop a small piece of red and of blue litmus into 
each solution. Examine the litmus. (See page 260.) 

Tabulate your results as indicated below: 



Name of 
salt 


Formula 


Effect on 
litmus 


Acid 
Basic or 
Neutral 


Hydrogen 

ion 
concent'n 


Hydroxyl 

ion 
concent'n 


Salt 
of 


Potassium 
carbonate 


K 2 C0 3 


Red to blue 


Basic 


Low 


High 


Weak acid 

Strong 

base 


Sodium 
Chloride 














































• 












































, 









14 

2. Write an equation for each of the above reactions which did not show 
a neutral effect on litmus. (See page 261.) 

3. Write an ionic equation corresponding to each equation in (2). 



7. FLAME TESTS 

(Chapter 25) 

Apparatus — Platinum (or nichrome) wires. Burner. Cobalt glass. 

Material- — Salts of sodium, potassium, lithium, calcium, barium, strontium, 
copper. Dilute hydrochloric acid. 

For this experiment it is desirable to have a platinum wire for use with 
each salt tested. In this case, the glass tube (in the end of which the platinum 
wire is held) should be inserted through a one-hole stopper. This stopper is 
then inserted into the test tube, and the test tube labelled with the name of the 
solution it contains. The wire should reach into the liquid. Since this arrange- 
ment makes it possible to test only this one salt on this wire, time need not be 
lost in cleaning the wire after every test. If separate wires are not available, 
the platinum wire may be cleaned after testing a salt by alternately dipping 
it into a little clean dilute hydrochloric acid, and heating, until all trace of the 
colour of the salt tested has disappeared. 

Test — Remove the wire from the solution in the test tube and hold it at 
the edge of a colourless flame. Colour? Repeat several times. Observe flames 
of the following salts through a cobalt glass in addition to the regular tests: 
Sodium, potassium, a mixture of sodium and potassium (p. 403). Put the 
corner of a copper wire gauze into a little dilute hydrochloric acid and hold in a 
colorless flame. Result? Powder a little blackboard chalk and apply the 
flame test. Colour? Clean the wire thoroughly (if necessary) at the end of 
each test. 

A salt of strontium may be tested if desired. 

Record your results in the following form: 



Element 


Formula of 
Compound 


Colour of 
Flame 


Colour through 
Cobalt glass 


Sample of 
Colour 































































15 

8. ALUMIMUM 

(Chapter 26) 

Apparatus — Test tubes and racks. Burner. Beakers (2). Blow pipe. 

Materials — Aluminum foil. Hydrochloric acid. Sodium hydroxide solu- 
tion. Splint. Aluminum sulphate. Ammonium hydroxide. Lime water. 
Charcoal block. Cobalt nitrate solution. Cotton cloth. Logwood. 

1. Action of strong acid and base. 

Into each of two test tubes put about 1 sq. cm. of aluminum foil. To 
one add about 2 cc. of hydrochloric acid (concentrated), and to the other some 
caustic soda solution. Warm gently for a few moments. Results? Equations? 

Test any gas that is generated, with a burning splint. Result? (See page 
415.) 

2. Action of cautic soda on aluminum hydroxide. 

Half fill each of two test tubes with a solution of aluminum sulphate. To 
the first add a few drops of ammonium hydroxide solution, then several cc. 
Result? Equation? 

To the second add a little caustic soda solution, then an excess. Result? 
Equations? 

3. Purification of water by aluminum hydroxide. 

Prepare some murky water by stirring a handful of soil in water. Allow 
the mixture to stand a few minutes. Then pour off some of the cloudy water 
into each of two beakers. To one add about 2 cc. of alum solution or solution 
of aluminum sulphate, and then several cc. of lime water. Allow to stand and 
observe at five minute intervals. The second serves as a control for purposes 
of comparison. Results? Equation? (See page 420.) 

4. Test for aluminum ion. 

Using a small coin, wear a depression near one end of a charcoal block. 
Fill this with some aluminum compound (moistened to a paste) and heat with 
the oxidizing flame of a blowpipe. Moisten the residue with a few drops of 
cobalt nitrate solution. Heat strongly again. A blue colour indicates aluminum. 

5. Aluminum hydroxide as a mordant. 

Cut two pieces of white cotton cloth. Mordant one by soaking it in a solu- 
tion of aluminum sulphate and then in ammonium hydroxide, squeezing out the 
excess liquid after each soaking. Now place both pieces of cloth in a beaker 
containing logwood or alizarin solution. Boil for a few minutes. Wash the 
cloths and examine. Results? Equation? (See page 635.) 

9. COPPER 

(Chapter 28) 

Apparatus — Test tubes and racks. 

Material — Several salts. Nail. Potassium ferrocyanide. Ammonium 
hydroxide. Copper strip. Silver nitrate solution. An iron salt. 

1. Colour of cupric ion. 

Dissolve, in separate test tubes, small quantities of copper sulphate, copper 
chloride, copper bromide, sodium chloride and potassium nitrate. Colours? 



16 

Write ionization equation for each of the above and state the colour of each 
ion formed. (See page 459.) 

2. Tests for copper ion. 

Place a clean nail in a solution of copper sulphate. Allow to stand. Result? 

Add some potassium ferrocyanide solution to a dilute solution of copper 
sulphate. Result? Equation? 

Add ammonium hydroxide solution, drop by drop, to a solution of copper 
sulphate, till no further change occurs. Results? Equations? (See page 459. J 

Suspend a strip of copper in silver nitrate solution in a test tube. Observe 
frequently. Results? Equation? 

Try another strip of copper in a solution of an iron salt. Result? (See 
page 396.) 

10. BAKING POWDERS 

(Chapter 30) 

Apparatus — Test tubes and racks. Stand. Clamp. Delivery tube. 
Burner. Beakers (250 cc). 

Materials — Baking soda. Lime water. Cream of tartar. Dilute hydro- 
chloric acid. 

1. Action of heat on baking soda. 

Put about 2 grams of bicarbonate of soda in a test tube and support this 
in an almost horizontal position on a stand. Arrange a delivery tube so that 
it leads into lime water in a test tube. Heat the bicarbonate gently. Result? 
Equation? (See page 503.) 

2. Action of a strong acid on baking soda. 

Into a test tube put a small quantity of sodium bicarbonate. Have a 
stopper and delivery tube arranged as in part (1). Add a few drops of dilute 
hydrochloric acid to the salt and replace the stopper quickly. Result? Equation? 
(See page 366.) 

3. Reaction of a baking powder. 

Weigh out 2 gr. of potassium bitartrate (cream of tartar). Calculate the 
weight of sodium bicarbonate needed to react with it (p. 365). Weigh out this 
quantity and mix the two salts. Put half the mixture into a beaker containing 
100 cc. of cold water, and the other half into 100 cc. of hot water. Results? 
Equations? 

11. CALCIUM COMPOUNDS 

(Chapter 31) 

Apparatus — Test tubes and racks. Wire gauge. Burner. Evaporating 
dish. Broken test tubes. 

Materials — Chalk. Litmus. Plaster of Paris. Quick lime. Sand. Port- 
land cement. Hydrochloric acid. Lime water. 

1. Lime. 

Place a piece of marble or chalk about the size of a pea on a wire and heat 
strongly for 20 minutes. Allow to cool. Now put it in a test tube and add a 



17 

little water. Note any temperature change. Test with red and blue litmus. 
Result? Equation? (See page 511.) 

2. Plaster of Paris. 

Put a heaping tablespoonful of Plaster of Paris in an evaporating' dish. 
Add just enough water to make a thick paste. When hardened to the proper 
consistency, mould rapidly into any desired shape. Allow to harden. Equation? 
(See page 516.) 

3. Mortar. 

Mix together small quantities of quicklime and sand in the proportions of 
1 to 2 by volume. Add water to make a thick paste. Pour into a broken 
(useless) test tube and allow to stand for a week. Break away the test tube 
and examine. Result? (See page 515.) 

4. Cement. 

Mix some Portland cement and fine sand in the proportions of 1 to 3 by 
volume. Add enough water to make a thick paste. Pour into a broken test 
tube or paper box and allow several days to harden. Result? (See page 551.) 

5. Hard water. 

Pass carbondioxide (prepared by the action of an acid on a carbonate) 
into lime water till the precipitate at first formed clears. Equations? Now 
boil some of this clear water. Result? Equation? (See page 521.) 



12. COMPOUNDS OF IRON 

(Chapter 32) 
Apparatus — Test tubes and rack. Burner. 

Materials — Ferric salts. Ferrous salts. Sodium hydroxide. Ammonium 
thiocyanate. Potassium ferrocyanide. Potassium ferricyanide. Nitric acid. 
Dilute sulphuric acid. Steel wool. Dilute hydrochloric acid. 

1. Tests for a ferrous salt. 

Half fill each of four test tubes with a dilute solution of a ferrous salt (freshly 
prepared). Into the test tubes put, respectively, a few drops of the following 
solutions: Sodium hydroxide, ammonium thiocyanate, potassium ferrocyanide, 
and potassium ferricyanide. Colours? Equations? (See page 529.) 

2. Tests for a ferric salt. 

Repeat the prodecure outlined in (1) but use a ferric salt instead of a ferrous 
salt in the original test tubes. Colours? Equations? 

Tabulate the results of (1) and (2) in the form shown below, giving the 
name of the salt formed, its formula and its colour. Indicate any precipitates 
formed by an arrow (pointing downward). 





Ferrous salt 


Ferric salt 


Sodium hydroxide 
NaOH 






Ammonium thiocyanate 

NH 4 CNS 






Potassium ferrocyanide 

K 4 Fe(CN) 6 






Potassium ferricyanide 

K 3 Fe(CN) 6 







18 

3. Oxidizing a ferrous salt. 

To 5 cc. of a solution of ferrous sulphate, add 1 cc. of dilute sulphuric 
acid, and then a few drops of nitric acid (concentrated). Boil (CAUTION!). 
Test a small quantity of the resulting liquid for ferrous and ferric ions. Result? 
Equations? (See page 527.) 

4. Reducing a ferric salt. 

To 10 cc. of a solution of ferric chloride add several strands of steel wool 
(or mossy zinc). Pour in 2 or 3 cc. of dilute hydrochloric acid. Warm gently. 
Test small quantities of the solution from time to time for ferrous and ferric 
ions. Result? Equation? (See page 527.) 



13. BORAX BEAD TESTS 

(Chapter 33) 

Apparatus — Burner. Platinum wire. Metallic compounds to be tested. 

Ordinary borax (hydrated sodium tetraborate) swells when heated owing 
to the evaporation of the water of crystallization, then melts to a colourless glassy 
bead, containing the oxide of boron, B 2 3 . This oxide combines when heated 
with several metallic oxides imparting characteristic colours, by which the metals 
are identified. (See page 555.) 

Bend the end of a platinum wire around the end of a pencil into a loop 
about 3 mm. in diameter. Heat the wire, and while still hot dip it into some 
powdered borax. Again heat strongly. Continue the process till a globular 
bead has been formed. 

1. Oxidizing flame. 

Pour a little cobalt nitrate on a watch crystal. Touch the bead while 
hot to a tiny particle of cobalt nitrate. Heat in the oxidizing (outer) flame of 
the burner till the bead is red hot and the colour uniform. Observe the colour 
while hot, and when cold. If the bead is too dark, repeat using less of the 
nitrate. To clean the bead, dip while hot into water and brush the particles 
away. 

Forming a new bead each time, test the following compounds: Ferrous 
sulphate, manganese dioxide, nickel nitrate, chromium sulphate. Other com- 
pounds of these metals may be used. 

2. Reducing flame. Repeat the experiment using the reducing flame 
(tip of the inner cone). 

Tabulate your results as shown below: 



Metal 


Com- 
pound 
used 


Formula 


Colour in oxidizing 
flame 


Colour in reducing 
flame 


Hot 


Cold 


Hot 


Cold 


Cobalt 














Iron 




, 










Manganese 














Nickel 














Chromium 















3. Clean the bead when you have completed the tests. 



19 

14. DETERMINATION OF ACIDITY OF VINEGAR 

(Chapter 35) 

Apparatus — Burette (50 cc). Pipette (10 cc.) Ring standard clamp, 
beaker (250 cc.). 

Materials — Vinegar or cider. Distilled water. O.IN solution of sodium 
hydroxide. Phenolphthalein solution. 

(For this experiment a O.IN solution of sodium hydroxide should be pre- 
pared in advance as follows : Dissolve 4 grams of caustic soda in distilled water. 
Dilute to 1 liter. Stir well.) 

Using the pipette, put exactly 10 cc. of the vinegar (or cider) into a beaker. 
Add about 50 cc. of water. Add a few drops of phenolphthalein. Fill the 
burette with the sodium hydroxide solution and titrate by running the basic 
solution into the beaker, drop by drop, till the end point is reached (as in exp. 4). 
Record the volume of base used (final reading minus first reading in the burette) . 

Repeat the titration and again record the volume of base used. 
Calculations : 

Concentration of sodium hydroxide solution O.IN 

Wt. of sodium hydroxide in 1 cc. of solution 0.004 g. 

Volume of basic solution used: 

first titration cc. 

second titration ..cc. 

average cc. 

Weight of acetic acid in 10 cc. of vinegar g. 

Weight of acetic acid in 100 cc. of vinegar g. 

Normality of vinegar. 

15. FOOD INGREDIENTS 

(Chapter 36) 

Apparatus — Test tubes and rack. Burner. Mortar and pestle. Por- 
celain crucible cover. 

Material — Starch. Glucose. Cane sugar. Fat. Oil. Egg. Oatmeal. Cheese. 
Iodine solution. Fehling's solution. Hydrochloric acid. Sodium carbonate. 
Litmus. Benzine. Nitric acid (cone). Ammonium hydroxide. 

1. Test for starch. 

Put a pinch of starch in a test tube. Half fill with water. Shake and boil. 
Cool and add a drop of iodine solution (diluted tincture of iodine in potassium 
iodide solution). Colour? (See page 602.). Test freshly cut pieces of potato 
and bread with iodine solution. 

2. Test for sugar. 

Dissolve 1 cc. of glucose in 10 cc. of water. Add 5 cc. of Fehling's solution 
and boil for a few minutes. The red precipitate formed is a test for glucose or 
fructose. (See page 603.). 

Repeat using a solution of cane sugar (sucrose). Result? Now add a 
few drops of dilute hydrochloric acid to a solution of cane sugar in a test tube. 
Heat to boiling. Cool. Now neutralize by adding a little powdered sodium 
carbonate (test with litmus). Test as above with Fehling's solution. Result? 
(See page 605.) 



20 

3. Test for fats and oils. 

Place a drop of oil on a piece of paper. Hold to the light. Result? 

Put a spoonful of cornmeal or crushed peanuts in a test tube. Keeping 

away from a flame, add enough benzine or ether to cover. Shake. Allow to 

stand. Pour a few drops of the clear liquid on a piece of paper. Examine 
against the light. Result? (See page 606.) 

4. Test for proteins. 

Place a little of the white of a hard-boiled egg in a test tube. Add a few 
drops of nitric acid (cone). Colour? Wash off the acid with water. Add a 
few drops of ammonium hydroxide. Colour? (See page 608.) 

5. Test for mineral matter. 

Place half a teaspoonful of oatmeal on a porcelain crucible cover. Heat 
strongly (under a hood), till all the carbon is burned away. Result? 

Samples of food such as bread, cheese, beans, lean meat, can be tested for 
each of the above ingredients. If these tests are made, tabulate your results. 

EXAMINATION FOR THE ACID RADICLE 

The following scheme is for the identification of the anions : 
Carbonate (C0 3 ), sulphite (S0 3 ), sulphide (S ), chloride (CI ), bromide (Br ), 
iodide (I ), nitrate (N0 3 ), phosphate (P0 4 ), sulphate (S0 4 ), nitrite (N0 2 ). 

Group A 

To a portion of the original solution, add dilute HN0 3 . No gas evolved. 
Pass on to Group B. 
If a gas is evolved: 

(1) Gas is odorless — test with lime water. If carbondioxide is present, 
this indicates a carbonate. 

(2) Gas has sharp odour — S0 2 — a sulphite. 

Confirm by holding a drop of K 2 Cr0 4 on a g'ass rod in the gas — drop 
turns pale green. 

(3) Gas has odour of rotten eggs — a sulphide. 

Confirm by holding paper soaked with lead acetate solution in gas. 
Paper turns brownish-black. 

Group B 

To a portion of original solution, add AgN0 3 solution. No ppte. Pass 
on to Group C. 

A ppte. is produced: 

(1) White ppte. — a chloride. 

Confirm by adding NH 4 OH in excess. Ppte. dissolves. 

(2) Cream-colored ppte. — a bromide. 

Confirm by adding a little Mn0 2 and cone. H 2 S0 4 to original solution 
and warming. Brown fumes of bromine. 

(3) Yellow ppte. — an iodide. 

Confirm with Mn0 2 and H 2 S0 4 as above. 
Yiloet vapors of iodine. 



21 

Group G 

Place a square of clean glass on a sheet of white paper on the desk. On 
the glass put close together a drop of the solution to be tested, a drop of ferrous 
sulphate solution and a drop of cone. H 2 S0 4 . With a glass rod bring these 
together. A brown colour (not to be confused with the shadow of the liquid 
on the paper) — a nitrate. 

No brown colour, pass on to Group D. 

Confirm by adding a little cone. H 2 S0 4 , and some copper turnings to original 
solution. Warm. Brown fumes. 

Group D 

To about 2 cc. of ammonium molybdate in a test tube, add about 1 cc. of 
original solution to which a little HN0 3 has been added. If no immediate 
reaction, warm a little (do not boil) and allow to stand. 

No yellow ppte. Pass on to Group E. 

Fine yellow ppte.— a phosphate. 

Confirm by adding AgN0 3 to original (neutral) solution. Yellow ppte. 
soluble in HN0 3 or in NH 4 OH. 

Group E 

To a portion of the original solution add BaCl 2 and dilute HC1. 
White ppte. — a sulphate. 
Confirm by boiling. Ppte. remains. 

Group F 

If the salt is insoluble in water treat as follows: 

Put a small quantity of the salt in a test tube and add a little cone. H 2 S0 4 . 
Warm. 

(a) Gas colourless — identify as in Group A above. 

or if cloudy fumes are produced on breathing across mouth of test 
tube — a chloride. 

(b) Gas brownish — a nitrite. 

After trying several of the tests, ask your teacher for an unknown salt 
(solid). Use part of this salt for determination of the cation and part for deter- 
mination of the anion. Keep a complete record of the tests you make, record- 
ing all negative as well as positive results. 

FIRST AID 

In case of an accident or injury, notify your instructor at once. 

Treatment for common types of injuries in the laboratory. 
Acids— 

On the skin — Wash with plenty of water. If severe, dress with a paste of 
sodium bicarbonate. 



22 

On the clothing -Saturate with dilute ammonium hydroxide. 
Internal — Drink lime water, milk of magnesia or baking soda solution. 

Bases— 

On the skin or clothing — Wash with plenty of water. Then apply a boric 
acid solution. Wash again. 

Internally — Drink juice of a lemon or orange. 

Burns — 

Apply a paste of sodium bicarbonate and water. 

Cuts^ 

Clean with water. Apply tincture of iodine or hydrogen peroxide. Band- 
age. 



23 



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PHYSICS 1 and 2 

TEXTBOOK: Modern Physics: Dull (Holt & Co.). 

The following supplementary books, prepared by the publishers to accom- 
pany the textbook, are available from the School-Book Branch. They are 
listed here as material for teachers' and students' reference, but students are 
not required to provide themselves with copies of any of them. The Work- 
book Manual and Answer Book for Teachers will be supplied only to teachers. 

Physics Workbook 

Answers and Manual Accompanying the Physics Workbook 

Laboratory Exercises in Physics 

Tests in Physics, Series II 

Answer Book for Teachers 

Classroom Library 

Every classroom for Physics 2 should be provided with a library of reference 
books for the use of teacher and students. A suitable list of such books may 
be found in the High School Regulations for the Year Ending July 31, 
1944; and these books may be had from the School-Book Branch. 

PHYSICS 1 
Division of Material: 

The following material from the textbook has been selected for the Physics 
1 course: 

Unit 1 — Matter and Mechanics ...Pp. 1- 85 

Unit 2— Molecular Physics Pp. 87-105 

Unit 6— Heat (Chapters 9 and 10).. Pp. 203-228 

Unit 7— Sound _ .. Pp. 285-319 

Unit 8— Light Pp. 321-400 

Teachers are advised to make the course, especially in " Sound " and " Light," 
as practical as possible, and to omit the more difficult mathematical problems 
and the geometrical treatment of 'Might." 

See also the "Special Notice to Teachers/' below. 

The following division of time during the school year is recommended: 

For Unit 1 10 weeks 

Unit 2 3 weeks 

Unit 6 4 weeks 

Unit 7 5 weeks 

Unit 8 10 weeks 

Review... 4 weeks 



Total ....36 week. 



PHYSICS 2 

The following material from the textbook has been selected for the Physics 2 
course: 

Unit 3— Force and Motion. ...Pp. 107-162 

Unit 4— Work— Power— Energy Pp. 163-174 

Unit 5— Machines Pp. 175-202 

Unit 6— Heat (Chs. 11, 12 and 13) ...Pp. 229-284 

Unit 9 — Magnetism and Electrostatics Pp. 401-430 

Unit 10— Current Electricity Pp. 431-528 

Unit 11 — Radio and Radiations ... Pp. 529-564 

Unit 12 — Transportation Pp. 565-598 



25 

Foreword 

Practical and experimental work has exactly the same place in the course 
in Physics 2 as in Chemistry 2; and accordingly the statement made in the 
"Foreword"' on page 3 of this Bulletin could properly be repeated here. 

The Outline for Practical Work, which follows, is offered for the pur- 
pose of saving time for teachers and students. The field of choice in practical 
activities and exercises is possibly larger for Physics 2 than for Chemistry 2. 
Teachers and students may organize projects to be carried on outside the class- 
room, and may in other ways devise practical exercises to take the place of some 
of those suggested. The main thing to be considered is the need for tying to- 
gether the instruction in theory and the practical exercises, projects and 
activities. 

The experimental work will consist partly of experiments demonstrated 
by the teacher and partly of experiments designed for individual work or for 
groups of two or three students working together. 

The twenty experiments in this outline have been selected for individual 
work on the basis that each requires some quantitative observations and in- 
volves some definite calculations leading to a specific result. Completed ex- 
periments, with a reasonable degree of accuracy, should be expected of all 
students. 

The experiments are in two groups, the first ten dealing with Mechanics 
and Heat, the second ten dealing with Magnetism and Electricity. A minimum 
of seven in each group should be done by each student. 

Owing to the fact that much of the apparatus for these experiments is 
expensive, it is suggested that only one or two sets of apparatus for each experi- 
ment should be provided. This will make it necessary for groups to perform 
the experiments in rotation. 

The list of apparatus provided below is based on the assumption that 
many of the experiments will be running concurrently where larger classes 
are involved; hence the necessity for several of such instruments as ammeters 
and voltmeters. An adequate supply of such equipment should be built up in 
each school over a period of years. This list does not include demonstration 
equipment. There is practically no limit to the amount of equipment a teacher 
will find useful in teaching this course. It can be added to indefinitely, but 
much of it may be improvised or constructed by students at home or in the school 
shop. 

List of Apparatus for Physics 2 

3 spring balances (250 gm.) 

3 Spring balances (2000 gm.) 
*1 Spring balance (15 kgm.) 
*1 parallelogram of forces board 

11" perforated metal ball 

3 large retort stands and clamps (iron) 

1 wooden stand and clamp 

1 board for friction experiments 

1 set of kilogram weights on hook 

1 set of gram weights on hook 

1 wheel and axle 

1 metre stick 

1 inclined plane and car 

3 insulated calorimeters 

6 thermometers (centigrade) 



26 

2 thermometers Fahrenheit) 

3 physical balances 

3 sets of metric weights 

1 aluminum block for specific heat experiment 
*1 Liebig's condenser 

*1 distilling flask 

*1 boiler for heat experiments 

2 water traps 

1 Regnault's dewpoint hygrometer 

1 Wet and dry bulb hygrometer 

6 bar magnets (6" long) 

1 horseshoe magnet 

1 box of fine iron filings 

1 roll of blue print paper 

1 grooved board for bar magnets 

1 demonstration Voltaic cell 
6 zinc elements for the above 

4 copper elements for the above 

2 carbon elements for the above 

3 Daniell cells 
3 dry cells 

3 voltmeters (low range, D.C. graduated in tenths) 

3 ammeters (low range, D.C. graduated in tenths) 
*1 voltmeter (A.C. 0-150 volts) 
*1 ammeter (A.C. 0-10 amps.) 

1 resistance box (plug-in type) 

1 resistance box (dial type) 

1 set of assorted standard resistances 

1 variable resistance (0-3 ohms) 

1 storage battery (6 volts) 

6 knife switches (s.p.s.t.) 

1 Wheatstone bridge (slidewire type) 

1 D'Arsonval type galvanometer 

12 pietenpol connectors 

6 test clips 

1 Hoffman's Electrolysis apparatus 

1 mercury barometer 

1 galvanoscope (multiple coil type) 

6 small compass needles (enclosed) 

1 demonstration compass needle (open) 
*1 St. Louis type demonstration electric motor 
*3 40-watt lamps (Mazda) 
*1 25-watt lamp (Mazda) 
*1 60-watt lamp (Mazda) 
*1 100-watt lamp (Mazda) 
*1 16-c.p. carbon lamp 
*1 32-c.p. carbon lamp 
*1 transformer-rectifier (6 volt) 

In addition to the above, assorted beakers, flasks, test tubes, measuring 
cylinders, glass tubing, rubber tubing, rubber corks, tripods, bunsen burners 
or spirit lamps, reagent bottles, battery jars, porous cups, wire gauze and other 
chemical equipment will be needed. 

Special chemicals for these experiments include: 

Sulfuric acid 
Nitric acid 
Hydrochloric acid 



27 

Mercury 

Copper sulfate 

Sodium dichromate 

Ether 

Ethyl alcohol (95%) 

Methyl alcohol 

*The apparatus marked with an asterisk is less essential or expensive equip- 
ment which is required for only one experiment and could be omitted. 

EXPERIMENT 1 

The Parallelogram of Forces 

Object: To demonstrate the proposition known as the parallelogram of 
forces, and to calculate the equilibriant of two forces acting at any angle. 

Reference: '/Modern Physics," Sections 131-136. Study the definitions 
of "Resultant of two Forces acting at any angle/' and "Equilibriant of two or 
more forces. " 

Apparatus: Three spring balances graduated in grams, a small iron ring 
(diameter 1"). string, drawing paper, thumb tacks, either three 3" nails or 
perforated board and pins as listed in science catalogues. 

Procedure: If the prepared board is available, tie three lengths of string 
to the iron ring, place the three pins in holes at the extreme ends of the board 
and adjust the three spring balances on the board so that when the three strings 
are tied to their hooks and their rings are placed over the pins they will each 
register a tension at about the middle of their scales. 

If the board is not available, use the three 3" nails driven firmly into an 
old table or bench so that they form a triangle with sides about three feet long. 
The spring balances are attached to these nails and to the iron ring by means of 
lengths of string, with the iron ring approximately in the centre of the triangle. 
Place a sheet of drawing paper under the strings with the iron ring in the centre 
and attach to the board or table by means of tacks. Make sure that the balances 
are stretched with as little friction as possible against the board or pins. Using a 
set square, mark two points vertically below each string, one at each end, so 
that when these points are joined with straight lines they will exactly represent 
the direction of each string. 

Now read each spring balance as accurately as possible and record its value 
in grams on the paper along the string attached to it. Remove the balances 
from the pins, join up the points on the paper so that they meet in a point. 

Along two of the lines mark off lengths proportional to the readings of the 
spring balances. A suitable scale might be 1 cm. to represent 20 gm. Taking 
these two lengths as the two adjacent sides of a parallelogram, complete the 
parallelogram using a compass to mark off equal opposite sides. 

Draw the diagonal of the parallelogram, measure its length in centimetres 
and express it as a force in grams on the same scale as you used for the sides of 
the parallelogram. 

Results: Is the diagonal of your parallelogram in the same straight line 
as the line representing the pull of the third balance? If your work was done 
accurately and the balances registered correctly with the minimum of friction, 
this should be the case. 

Does the length of the diagonal in centimeters represent the same value in 
grams as the third balance? 



28 

Letter your diagram ABCD etc., and state in the lower right-hand corner 
of the paper which lines represent which forces, which is the resultant force and 
which is the equilibriant. Write a statment in ink of the proposition which 
you have thus demonstrated. 



EXPERIMENT 2 

The Simple Pendulum 

Object: To study the laws governing the oscillation of a pendulum and to 
find the value of g, the acceleration due to gravity. 

Reference: " Modern Physics," Sections 162-166. Study the definitions 
of " single vibration," " complete vibration," " period, " " amplitude of vibra- 
tion." 

Apparatus: About 4 feet of strong thread, one inch metal ball perforated 
through the centre, or other suitable pendulum bob, clamp, stop watch or 
metronome. An ordinary watch with a seconds hand may be used if a stop 
watch or metronome is not available. 

Procedure: (a) Tie the thread to the metal ball and secure the other 
end by means of a clamp, adjusting the length of the pendulum so that it is 
exactly one meter from the point of suspension to the centre of the bob. Pull 
the bob to one side through a small arc, not more than three inches, and release 
it. When it is swinging uniformly, take the time in seconds for it to make 30 
single vibrations. Two students working together can do this quite accurately 
with an ordinary watch if one watches the pendulum and give the time for 
starting and stopping the count, whilst the other observes the seconds hand 
of the watch. 

Repeat the experiment with the pendulum swinging over a larger arc, 
say, six inches, and again with an arc of about one foot. Keep a record of your 
results. 

(b) Shorten the thread so that the effective length of the pendulum 
is 25 cm., and determine the average period of oscillation; i.e., the time for one 
complete vibration of the pendulum. Use a small arc and take the average 
time for twenty complete swings, using several tries. Record all results. 

(c) Repeat the experiment using a pendulum with an effective length 
of 64 cm. Record the average value for the period of oscillation. 

Results : Tabulate your results from experiment (a) thus : 



Exp. No. 


Amplitude 

(approx.) 


No. of single 
vibrations 


No. of 
sees. 


Period for 
single vib. 













What is the relation between the time of vibration and the amplitude? 
State the^ result as a law. (See Section 163 of textbook.) 



29 

Tabulate your results from experiments (b) and (c) thus : 



Exp. No. 


Length 


V Length 


Period for 
complete vib. 


Value of g. 


a 
b 
c 











How is the time of vibration related to the length of the pendulum? 
this as a law. (See Section 163 of textbook.) 

Determine the value of "g" by using the formula, 

T=2TV- 

g 



State 



EXPERIMENT 3 

The Coefficient of Friction 

Object: To determine the coefficient of sliding friction and to compare 
it with rolling friction. 



Reference: "Modern Physics," Sections 183-190. 
and the definition of "coefficient of friction." 



Study Section 187 



Apparatus: A board 5 ft. long and 4 or 5 in. wide, preferably of fir or other 
hard wood, planed and smoothed with sandpaper, a small block of the same 
material about 3" x 5" x 1", spring balance, kilogram weights, small experi- 
mental car, string. 

Procedure : (a) Insert a small hook in the centre of one end of the wooden 
block, suspend it from the spring balance and record its weight in grams. Lay 
the long board flat on a bench and rub the small wooden block over it several 
times. Attach a string to the hook on the block and tie the other end to the 
balance as in Fig. 221 of the textbook. Pull gently on the balance and tap on 
the board so that the block just starts moving. Read the balance at this 
instant. Repeat several times and determine the average force of friction. 
Record all readings in tabular form. 

Now place a kilogram weight on the wooden block and repeat the experi- 
ment, again recording the readings of the balance and determining the average 
force of friction. 

(b) Place a stop against one end of the board and lay the wooden block 
on the board. Raise the other end of the board until the block begins to slide 
down the slope. Note the approximate angle of repose; i.e., the greatest angle 
at which the block remains in equilibrium on the inclined plane. Place a support 
under the board and adjust the slope of the plane so that when gently tapped 
the block will begin to slide down the slope. Measure the vertical height of the 
slope and the length of the base line along the table. For accurate measure- 
ment, the slope of the triangle must be produced and the exact point at which 
it meets the table marked. The dimensions of the right-angled triangle should 
be carefully recorded and the angle of the plane at the base determined with a 
protractor. 

(c) Lay the board flat and place the trolley car on it. Gently raise the 
board at one end until the car begins to move evenly down the slope. Deter- 
mine the height and base of the triangle so obtained as before. 



30 

Now lock the wheels of the car with a wedge and repeat the experiment 
determining the dimensions of the slope down which the car slides with locked 
wheels. 

Results: Determine from the data of experiment (a) the coefficient of 
sliding friction as worked out in Section 187 of the textbook. 

Is the value the same when the block carried the kilogram weight? 

From the data of experiments (b) and (c) the coefficient of friction may be 
determined by the formula, 

Vertical height 



C.F.= 



Length of base 



How do the results of experiment (a) and (b) compare? These two 
methods should give approximately the same results. 

The coefficient of friction may also be obtained by determining the tangent 
of the angle of friction. That is, if the angle between the board and the table 
at the base is i, the coefficient of friction =tan i. The results of this method 
should again check with those obtained above. 

From the data of experiment (c) determine the coefficient of rolling friction 
and the coefficient of sliding friction. Which is the greater? 

Tabulate the results of experiments (a), (b), and (c) in three separate tables, 
setting forth the weights used, the force of friction, the dimensions of the slopes 
and the calculated coefficients for each set of values. 



EXPERIMENT 4 

Part A— The Wheel and Axle 

Object: To determine the mechanical advantage of the wheel and axle. 

Reference: "Modern Physics," Sections 214-215. Study the method of 
determining the mechanical advantage of the wheel and axle as given in Section 
214. 

Apparatus: An experimental wheel and axle may be obtained from scientific 
supply companies, or it may be simply constructed by obtaining two wooden 
spools or cylinders, one large and the other small, and gluing them together 
coaxially. Nails may be driven into the centre of each spool to form an axle 
which can rest in two short lengths of glass tubing for bearings. The wheel 
and axle should turn symmetrically on these bearings which may be lubricated 
with oil to reduce friction. A small hole bored diagonally through the rim of 
each cylinder will provide points of attachment for strings. A small tray to 
carry weights may be made from the lid of a round can with holes bored around 
its rim for the supporting wires or string. 

Procedure : Set up the wheel and axle and see that it turns without wobbling 
and with as little friction at the bearings as possible. Tie a string to the small 
wheel or axle and pass it around the circumference twice. To the other end 
of the string tie a 500 gm. weight. Tie a string to the large wheel and pass it 
around its circumference in the reverse direction to the string around the axle. 
Attach the tray, previously weighed, to the other end of this string. Now place 
weights in the tray until the wheel and axle remains in equilibrium with both 
weights hanging freely. Record the weights used and measure the diameters 
of the wheel and axle using a pair of calipers or dividers. Record the diameters 
in centimetres correct to the second decimal place. 



31 

Repeat the experiment using a 200 gm. weight and again with a 1000 gm. 
weight. Record the weights needed to balance these in each case. 

Results: Determine the theoretical Mechanical Advantage of this system 
from the dimensions of wheel and axle as explained in Section 214 of the text- 
book. Determine the actual mechanical advantage by dividing the weight by 
the effort for each experiment. Compare the theoretical mechanical advantage 
with the true mechanical advantage. 

Tabulate results as follows: 



Diam. of 
Wheel (cm.) 


Diam. of 
Axle (cm.) 


Theor. 
M.A. 


Weight 
Raised 


Effort 
W+w 


Actual 
M.A. 















Note: In above table W is the weight placed in the tray, w is the weight of the 
tray. 

Part B (optional). 

Reference: "Modern Physics," Section 223. 

Apparatus: Bicycle, kilogram weight, 15 Kgm. spring balance, 2" tape, 
metre stick. 

Procedure: Support the bicycle so that the back wheel will turn freely. 
Measure the diameter of the rear wheel in centimetres and determine its cir- 
cumference. 

Count the number of teeth in the two sprocket wheels and determine how 
many revolutions the rear wheel makes for one complete turn of the pedals. 
Check this experimentally. Measure the length of the pedal arm from centre 
to centre of the supporting axes. Determine the circumference of the circle 
traced out by a pedal in one revolution. This will give the distance the effort 
moves for one turn of the pedals. Determine the mechanical advantage of 
speed by dividing the distance of the resistance (circumference of rear wheel 
multiplied by the gear ratio) by the distance of the effort. The Mechanical 
Advantage of Force is the inverse of this. Why? 

Now attach a one-kilogram weight to the tire of the rear wheel so that it 
hangs down vertically below the outer circumference of the wheel. A piece 
of 2" tape placed over the outer circumference of the tire and supporting the 
weight is a good method of doing this. 

Hook the 15 Kgm. spring balance to the centre of the pedal and pull up- 
ward, taking the reading of the balance when the pedal is in a horizontal position. 
Divide the resistance (1000 gm.) by the effort. This gives the actual Mechanical 
Advantage of Force. 

Results : Tabulate all measurements and work out the actual and theoretical 
values for the Mechanical Advantage. 

Is there a big difference as between the theoretical and actual values? 
Is the bicycle an efficient machine? 

Note: If a 15 kgm. spring balance is not available the procedure may be 
reversed by tieing a large weight, say 10 Kgm. or 10 lb., to the pedal and attach- 
ing a small spring balance to the tire and pulling downwards to support the 
weight on the pedal. In this case, however, the weight of the spring balance 
must be added to its reading to determine the true value of the resistance. 



32 

EXPERIMENT 5 

The Inclined Plane 

Object: To determine the Mechanical Advantage of the Inclined Plane 
and to calculate the efficiency of this machine. 

Reference: "Modern Physics," Sections 216 and 217. Also review 
Sections 203 and 204. 

Apparatus: The Inclined Plane apparatus and car, weights, spring balance, 
metre stick, string. If the regular inclined plane apparatus as supplied by 
scientific manufacturing companies is not available, a smooth board 6 in. wide 
and five feet long and a model car made from a Meccano set with its bearings 
well lubricated may be used. 

Procedure: Set up the inclined plane at an angle of about 30°. Weigh 
the car on the spring balance and attach a long string to the hook. Place- it 
on the plane with a 500 gm. weight in it. Attach the string to the balance, 
pass the string over the pulley at the top of the plane and, applying a horizontal 
pull, determine the force required to pull the car up the slope. This force 
represents the effort required to overcome the pull of gravity and the friction. 

Take a second reading as the car runs slowly down the plane. This repre- 
sents the effort less the amount due to friction. The average of these two 
values gives the true force needed to overcome the pull of gravity down the 
plane. 

Measure a distance of 100 cm. along the lower edge of the inclined plane 
from the point where it contacts the table, and mark the distance on the edge 
of the plane. Measure the vertical height of the plane at this point from the 
table. 

Results: Repeat the experiment twice changing the angle of the plane 
for each trial. 

Tabulate all data as follows: 



Exp. 

No. 


Effort + 
Friction 


Effort - 
Friction 


Average 
Force 


Resistance; 
i.e., Weight 


Resistance 
Effort 


1. 
2. 
3. 













Exp. 

No. 


Length 


Height 


L/H 


Efficiency = |^X1 00 


1. 
2. 
3. 











Note: In the formula for efficiency given above E is the effort required 
to pull the car up the slope; i.e., Effort + Friction since, in this machine, useful 
work is only done when the weight is moved up the slope. 

What is the theoretical Mechanical Advantage of the Inclined Plane? 
What is the actual M.A.? What is the relation between the Mechanical Ad- 
vantage and the angle of the slope? 



33 

EXPERIMENT 6 

Determination of Specific Heat 

Object: To determine the specific heat of aluminum or other suitable 
metal by the method of mixtures. 

Reference: " Modern Physics," Sections 269-272, with particular reference 
to Section 271. 

Apparatus: Insulated calorimeter, thermometer, boiler or florence flask, 
burner, balance, set of weights, length of string, metal block or shot. 

Note: In this experiment the best results are obtained using a block of 
aluminum, since aluminum has a high specific heat. The usual method of heating 
some lead shot in a test tube supported in the neck of a florence flask containing 
boiling water may, however, be used. Care must be taken in this case to see 
that the lead shot is uniformly heated and that the thermometer inserted in the 
shot measures the average temperature of the shot. In reading the thermometer 
always estimate fractions of a degree to the nearest tenth. A small error in the 
thermometer reading can result in a large error in the specific heat. 

Method: Tie a piece of string to the metal block and weigh it. Or, if 
lead shot is to be used weigh out about 200 gm. of shot and transfer to a test 
tube. (A piece of heavy insulated wire twisted around the test tube serves 
both as a handle and as a means of supporting the test tube in the neck of the 
florence flask for heating.) 

Put the aluminum in a boiler half full of water with the string hanging 
outside. Heat the boiler with a bunsen or other burner. Weigh the calori- 
meter (the inside vessel only, if it is a double insulated calorimeter). Fill the 
calorimeter 2/3 full of water and weigh it again. The water used should be 
several degrees below room temperature. Take the temperature of the steam 
in the boiler. Stir the water in the calorimeter gently with the thermometer 
and record its temperature. 

Now raise the aluminum block so that it hangs only in the steam of the 
boiling water for a minute or so. Record the temperature of the metal as that 
of the steam in which it is suspended. Place the calorimeter in an insulating 
vessel supporting it in a fibre ring or cotton wool packing. Quickly transfer 
the aluminum block which should be quite dry to the calorimeter and take the 
resulting temperature, moving the block up and down to ensure thorough mixing 
of the water. If lead shot is used it may be quickly dumped into the water 
and stirred with the thermometer. 

Results: Tabulate all readings and weights and calculate the specific 
heat of the metal in the manner illustrated in Section 271 of the textbook. 

Compare your result for the specific heat of the metal with the value given 
in Table 6, Appendix B, " Modern Physics." 

Calculate the percentage error thus* ^ = — X100. 

Correct value 

In your conclusion to the experiment indicate the most probable sources 
of error. 

EXPERIMENT 7 

Heat of Fusion of Ice 

Object: To determine how many calories of heat are required to melt one 
gram of ice at its melting point. 



34 

Reference: "Modern Physics," Sections 277-279. Study the method 
of solving the problem on heat of fusion in Section 278. 

Apparatus: Insulated calorimeter, balance, weights, thermometer, ice, 
towel. The thermometer should be graduated in Centigrade degrees and 
should be read carefully to the nearest tenth of a degree. 

Procedure: Weigh the calorimeter — inside vessel only; fill it with about 
250cc. of water at 40°C; weigh again. The difference in the two weighings 
will give the weight of water taken. Break up the ice into pieces about one 
inch across. Take the temperature of the water in the calorimeter as accurately 
as possible having first placed the calorimeter in the insulating vessel. Remove 
excess moisture from the ice by wiping it with a cloth and introduce it into 
the calorimeter taking care not to lose any of the water by splashing. Stir the 
water constantly and take the temperature, adding more ice from time to time 
until the temperature is around 5°C. Stir until the ice is all melted and take 
the final temperature accurately. 

Now weigh the calorimeter to determine the weight of ice which has been 
added. 

Results: Following the method illustrated in Section 278 of the textbook, 
calculate the heat of fusion of ice in calories per gram. Tabulate all weights 
and temperatures neatly and show all calculations. Determine the percentage 
error in your result. Indicate the chief sources of error which you think may 
have arisen in your experiment. If these include errors of manipulation, repeat 
the experiment and try to get a more accurate result. 

EXPERIMENT 8 

Boiling Point 

Object: To determine the boiling point of certain liquids and to illustrate 
the process of fractional distillation. 

Reference: " Modern Physics," Sections 288-290. Study carefully the 
correct method of setting up a condenser as illustrated in Fig. 334, page 242 
of the textbook. 

Apparatus: A Liebig's condenser, distilling flask, 25 cc. graduate, ther- 
mometer, receiving flask, alcohol, 10% solution of salt water. 

Note: Wood alcohol, used for spirit lamps, is methyl alcohol, B.P. 66°C. 
Commercial grain alcohol is 95% ethyl alcohol, B.P. 78°C. Rubbing alcohol 
is chiefly ethyl with an admixture of methyl and other ingredients to "denature" 
it, 

Procedure: Set up the apparatus as shown in Fig. 334, p. 242 of the text- 
book. 

(a) Pour 100 cc. of tap water into the distilling flask and heat it to boiling. 
Have the bulb of the thermometer one inch from the surface of the water. When 
the thermometer remains steady take the temperature. If a mercury baro- 
meter is available take the atmospheric pressure in millimetres of mercury. 
Record these readings. Boil the water for two or three minutes and again 
record the boiling temperature. 

(b) Replace the water in the distilling flask by 100 cc. of alcohol and 
determine its boiling point. Use a clean receiver for each distillation. 

Pour the alcohol that has distilled over back into the flask and add lOOcc. 
of water. Determine the boiling point of the mixture. Continue to boil the 
mixture until 25 cc. has distilled over. Again record the boiling temperature. 



35 

Repeat with each of three more portions of 25 cc. of distillate, taking the 
temperature after each. Save the alcohol for future use. 

(c) Throw away the liquid left in the distilling flask, wash out flask and 
pour in 100 cc. of 10% salt solution. Determine the boiling point at intervals 
of three minutes as long as time permits. 

Results: (a) What is the boiling point of water? Does the B.P. rise with 
continued boiling? Refer to Table 9, Appendix B of the textbook. At what 
temperature should water boil at the recorded atmospheric pressure? How- 
does this check with your recorded B.P.? 

(b) What is the boiling point of pure alcohol? Is it ethyl or methyl 
alcohol? What is the boiling point of a mixture of alcohol and water? How 
does the boiling point change for the successive distillate fractions? How may 
this be explained? 

(c) Tabulate the data from experiment (c). Account for any change in 
the boiling point of the salt solution. 

EXPERIMENT 9 

Heat of Vaporization of Water 

Object: To determine the number of heat units required to change one 
gram of water into steam at its boiling point. 

Reference: " Modern Physics," Sections 291-293. Study the method 
of determining the heat of vaporization of water as worked out in Section 292. 

Apparatus: Steam boiler, water trap, rubber tubing, glass tube, balance, 
weights, insulated calorimeter, Centrigrade thermometer. 

Note: If a copper boiler is not available, fit up a florence flask half full 
of water, having a bent delivery tube passing through a one-holed rubber stopper. 
Heat it over wire gauze on a tripod. 

Procedure : Attach the water trap to the outlet pipe of the boiler or florence 
flask by means of rubber tubing. While the water is heating weigh the inside 
calorimeter vessel; fill it two-thirds full of water at about 5°C. (Snow or ice 
may be added to reduce the temperature of the tap water if necessary.) Weigh 
again to determine the weight of cold water in the calorimeter. 

Attach the glass tube to the lower end of the water trap by means of rubber 
tubing. Take the temperature of the water in the calorimeter reading accurately 
to tenths of a degree. Place the glass tube below the surface of water in the 
insulated calorimeter (Fig. 337, textbook), and pass a steady stream of steam 
into the calorimeter until the temperature has risen to about 40°C. Remove 
the delivery tube, stir the water in the calorimeter and determine its temperature. 
Now weigh the calorimeter to determine what weight of steam has condensed 
in the water. 

Take the temperature of the steam while the water is still boiling in the 
boiler. 

Results: Following the procedure illustrated in the textbook (Section 
292), tabulate all data and calculate the heat of vaporization of water. 

Compare your result with that given in table 6, Appendix B, of the text- 
book, and estimate the percentage error. Indicate the most probable sources 
of error in this method. 



36 

EXPERIMENT 10 

Dew Point and Relative Humidity 

Object: To determine the dew point and the relative humidity of the air 
in the room. 

Reference: " Modern Physics," Sections 300-306. See also " Elements 
of Physics," by Merchant and Chant, Sections 242-248, for a description of 
Regnault's dew-point hygrometer and the method of determining the relative 
humidity from the dew point. 

Apparatus: Either a Regnault's polished cup hygrometer or a highly 
polished metal cup, ether, ice, thermometer (Fahrenheit) ; either a hygrodeik 
or a wet-bulb thermometer prepared by tieing a fresh spirit lamp wick around 
the bulb of a Fahrenheit thermometer, the lower end of the wick dipping into 
distilled water. 

Note: If only Centigrade thermometers are available, refer to the table on 
p. 258, "Elements of Physics," by Merchant and Chant, for working out the 
relative humidity from the dew point. 

Procedure: (a) Using Regnault's hygrometer. Pour into the polished 
cup about 5 cc. of ether. Adjust the thermometer, bent delivery tube and 
straight exit tube in the cork so that the bent delivery tube is below the surface 
of the ether but the outlet tube and thermometer bulb is above the ether. Attach 
an atomizer bulb to the bent delivery tube and gently force air through the 
ether so as to cause it to evaporate rapidly. Observe the drop in the thermometer 
and without breathing on the polished cup note the moment that a faint film 
of moisture appears on its surface. Immediately read the thermometer and 
record reading. Stop blowing air through the ether and watch the film of 
moisture on the polished cup. Record the temperature at which the film dis- 
appears. The average of these is the dew point. Repeat the experiment 
twice more and take the average value of the dew point. 

(b) A polished cup or tin can may be used as follows: Fill the cup one- 
third full of water at room temperature. Add ice and stir with a thermometer 
until a film of moisture appears on the metal cup. Record the temperature at 
which the film appears and when it disappears. The average is the dew point. 
Repeat the experiment twice, using a fresh supply of water and ice. 

Note: It may be necessary to add warm water to make the film disappear 
from the metal surface. 

In either method (a) or (b) record the room temperature. Using a hy- 
grodeik or wet-and-dry bulb hygrometer, determine the relative humidity by 
reading the two thermometers. The wet bulb should be gently fanned with a 
piece of stiff paper to obtain an accurate reading. Record the two readings. 

Results: (a) Having determined the dew point in Fahrenheit degrees, refer 
to Table 5, Appendix B," Modern Physics," and determine the moisture capacity 
in grains per cubic foot at the dew point and also at the temperature of the 
room. The relative humidity may then be determined by the following formula: 

t» , ,. TT .j.. Water Vapor capacity at dew point w<lrtrt 

Relative Humidity = T77— — == — • . . ■ £ X100. 

Water Vapor capacity at room temp. 

If a Centigrade thermometer has been used, the temperature may be con- 
verted into Fahrenheit readings, or the table referred to above in "Elements of 
Physics," by Merchant and Chant, may be used. 

From the wet-and-dry bulb thermometer readings determine the relative 
humidity by reference to Table 16, Appendix B, of "Modern Physics." 



37 

Compare your results for the relative humidity of the room by the two 
methods. If there is not a fairly close agreement (within 5%) by the two 
methods, indicate in your conclusion which method you consider to be the most 
accurate. 

EXPERIMENT 11 

Lines of Magnetic Force 

Object: To map the lines of force about magnets. 

Reference: " Modern Physics," Sections 510-513. Look up, in an en- 
cyclopedia or chemistry textbook, the method of preparing blue print paper. 
This makes a good chemistry project. The paper may be bought at little 
expense from a supply house. 

Apparatus: Two bar magnets, horseshoe magnet with armature, iron 
filings, sieve or perforated metal box, pan, pins, blue print paper, board 1 ft. 
square with grooves cut parallel to hold bar magnets and of the same depth as 
the thickness of the magnets. 

Procedure : Place a bar magnet in the grooved board in a part of the room 
where the light is subdued. Pin a sheet of blue-print paper (9 x 11 in.) with 
the sensitive side up on the board so that the bar magnet is below the centre 
of the paper. Sprinkle iron filings in a thin layer evenly over the surface of the 
paper. Tap gently with the fingers until the filings arrange themselves in the 
direction of the lines of force. Without disturbing the arrangement of the 
iron filings, hold the board so that the paper is exposed to direct sunlight for 
about five minutes. At the end of this time the paper should have acquired a 
brownish color. Remove the pins, shake off the filings into a pan, and develop 
the print by washing it in water until all the yellow color has disappeared. 

Spread the blue print on a pane of glass to dry, face down. 

Repeat the experiment with two bar magnets placed with like poles ad- 
jacent, with unlike poles adjacent, and with a horseshoe magnet. 

Results: When the blue prints are dry, label each, trim them to a suitable 
size and preserve them in your notebook. Compare the results with the dia- 
grams shown in your textbook. Are there any irregularities in the lines of 
force shown on your blueprints? Comment on the possible cause of these. 

Note: If time does not permit each group to do all of these, they may be 
divided up among the groups and the results put on display for the whole class 
to study. Other arrangements, such as two magnets placed at right angles 
in the form of a cross, or three bar magnets forming a triangle, or a magnet with 
a soft iron ring to illustrate shielding may be tried. 

EXPERIMENT 12 

The Voltaic Cell 

Object: To set up a simple voltaic cell and to study its action. 

Reference: " Modern Physics," Sections 545-550. 

Apparatus: A simple demonstration cell, consisting of a glass jar with 
removable clamps to support the elements, two zinc strips, copper strip, carbon 
rod, D.C. voltmeter (1-15 volts or lower) Daniell cell, amalgamating fluid, 
No. 18 insulated copper wire. 



38 

Note: The amalgamating fluid may be prepared in the chemistry lab. by 
dissolving 5 cc. of mercury in aqua regia (60 cc. of nitric acid mixed with 200 cc. 
of hydrochloric acid). 

Procedure: Prepare some dilute sulfuric acid, 1 part acid to 20 parts water; 
fill the glass jar one-third full with the acid and place a strip of zinc in it. What 
gas is given off? Complete the equation: Zn+H 2 S0 4 

Note the colour of the zinc after a minute or two. What impurity in the 
zinc causes this appearance? (See Section 549, textbook.) What is meant 
by local action and how is it related to this impurity? 

Dip one end of the zinc strip (2 or 3 in. of it) in the amalgamating fluid. 
Leave it for one minute, then remove, rinse and wipe dry. Describe its appear- 
ance. 

Now put the amalgamated zinc strip in the sulfuric acid. How does its 
behavior compare with the previous action of the zinc strip? Explain the 
advantage of coating the zinc with mercury. 

Remove the zinc strip from the acid, wash it and place it in a beaker or 
in the sink. Avoid spilling or splashing the acid; it is very corrosive. 

Place a copper strip in the acid. Is there any action? Repeat using a 
carbon strip. Any action? 

While the carbon is still in the acid, place the amalgamated zinc strip also 
in the acid but not touching the carbon. Is there any action visible when the 
cell is on open circuit? Attach the carbon and zinc strips to the terminals of 
the demonstration cell and attach the terminals to the voltmeter using the 
copper wire. Observe the action of the cell and note the strip from which 
hydrogen gas rises. Record this. Record also the reading of the voltmeter. 
This is the E.M.F. of the cell. 

Short-circuit the cell by joining the two terminals by a short length of 
heavy copper wire. Leave it for a few minutes, then remove the shunt wire 
and again read the voltmeter. Record this. What is the appearance of the 
carbon strip now? What is the name for this effect? 

Now lift the strips from the solution, wipe off the bubbles of gas and replace 
in the solution. Read the voltmeter and record. Does the voltage return 
to its original value? Again short-circuit the cell with the shunt wire until it 
is polarized. Add a few crystals of sodium or potassium dichromate to the 
sulfuric acid and stir. What is the effect of the dichromate crystals on the 
reading of the voltmeter? What kind of an agent is potassium or sodium 
dichromate? What is the effect on hydrogen? What is the essential property 
of a good depolarizer? 

If time permits, set up the Daniell cell as follows: In the porous jar pour 
dilute sulfuric acid (1 of acid to 20 of water). Place an amalgamated zinc 
strip in the acid. Place the porous jar in the glass battery jar and fill the latter 
with a saturated solution of copper sulfate to the same depth as the acid in the 
porous jar. Insert the copper plate in the solution of copper sulfate. Allow 
time for the liquid to soak through the porous vessel and determine the E.M.F. 
of the cell with a voltmeter. Record the reading. Short-circuit the cell with 
the copper wire as before for two minutes and again record the voltage. Does 
this cell polarize? 

Remove the copper plate and examine it. Is there a deposit on its surface? 
What is it? The action at the positive plate is represented by this equation: 
H 2 +CuS0 4 = H 2 S0 4 +Cu. 



39 

If the Daniell cell is to be left standing for future use connect it in series 
with a 40 ohm resistance. 

Results: Tabulate all observations and readings and summarize your 
conclusions as to the cause and remedy for (a) Local action, (b) Polarization 
in the voltaic cell. 

Draw a diagram of the Daniell cell and explain its operation. 



EXPERIMENT 13 
Grouping of Cells 

Object: To study the different ways in which cells may be grouped and to 
determine the advantage of one method over another. 

Reference: "Modern Physics," Sections 555-559. Study the rules which 
apply to (a) Cells in series, and (b) cells in parallel as listed in Section 558. 

Apparatus: Three Daniell cells or dry cells, voltmeter, ammeter, resistance 
coils, No. 18 insulated copper wire. 

Note: A gravity cell is a form of Daniell cell that may be used for this 
experiment. The simple voltaic cell is not suitable owing to polarization. 
Three dry cells may be used but since their internal resistance is very low, it 
may not be easy to show the advantage of parallel connections for certain resist- 
ances with them. 

Procedure: Connect a Daniell cell to the voltmeter by means of No. 18 
copper wire and determine the E.M.F. Disconnect the voltmeter and connect 
in an ammeter and determine the amperage without other external resistance. 
Record the voltage and amperage. Connect the cell to a resistance of about 
5-30 ohms and determine the amperage. 

Connect three Daniell cells in series (Fig. 607, textbook) and test the com- 
bined E.M.F. with a voltmeter connected across the outside terminals of the 
series group. Record the voltage. 

Now connect the three cells in series with the ammeter and a 40 ohms 
resistance. Record the amperage. Note that the external resistance of 40 
ohms is large compared with the combined internal resistance of the cells. 

Now connect the three cells in series directly to the ammeter. Record 
the amperage. In this case the external resistance, that of the ammeter and 
connecting wires, is quite low, less than the* internal resistance of the cells. 

Repeat the procedure using the three cells in parallel (Fig. 609, textbook). 
Record the voltage and amperage alone, and when the parallel group of cells is 
connected with the 40 ohm resistance in series with the ammeter. 

Results: Tabulate the data as follows: 



Grouping 


Voltage 


Maximum 
current 


Current with 
40 ohms R. 


Single cell 








Three cells 
in series 








Three cells 
in parallel 









From the tabulated results indicate which method of grouping gives the 
maximum current: (a) when the external resistance is large compared to the 
internal resistance, (b) when the external resistance is smaller than the internal 
resistance. 



40 

EXPERIMENT 14 

Ohm's Law 

Object: To determine the resistance of an unknown resistor by the appli- 
cation of Ohm's law. 

Reference: "Modern Physics," Section 553 and the first part of Section 
619. For a more detailed explanation of Ohm's law as used for the determin- 
ation of the resistance of a conductor, read " Elements of Physics," Sections 
535-536. Note Fig. 610 in " Elements of Physics" for the method of con- 
necting the apparatus for this experiment. 

Apparatus: Ammeter, voltmeter (these should be graduated in tenths), 
rheostat or resistance box, battery of 5 or 6 volts, No. 18 wire for connections 
or Pietenpol connectors, a length of resistance wire of unknown resistance as 
supplied by your teacher. This may be of any value between one ohm and 
30 ohms. 

Procedure: Connect in series the following: Battery, knife switch, rheostat 
or variable resistance box, unknown resistor, ammeter. Across the ends of 
the unknown resistor connect in parallel the voltmeter. Set the rheostat so 
as to include only a few turns of wire, or, if a resistance box is used, set it at one 
ohm. 

Close the knife switch and immediately take the readings of both voltmeter 
and ammeter, reading to the nearest hundredth of an ampere or volt. Note: 
If the instruments are graduated in tenths, this will involve estimating the 
fractions of a division by judging with the eye the approximate fraction and 
expressing it as tenths. This will give the second decimal point in your reading. 
The knife switch should not be left closed for more than a half minute at a time, 
as the resistors will heat up and the resistance change while you are reading 
the instruments. Record the readings in a table as shown below. With the 
knife switch open, change the position of the reheostat or set the variable re- 
sistance at 2 ohms and, closing the switch, again take readings of the ammeter 
and voltmeter. Repeat the experiment with a gradual increase in the resistance 
of the variable resistance taking readings of the ammeter and voltmeter each 
time. Obtain five sets of readings. 

Results: Tabulate all data as follows: 



Exp. No. 


Voltmeter 
Reading 


Ammeter 
Reading 


Resistance R _ E 
in ohms I 











Is the value for R, i.e. the unknown resistance, constant? 

Take the average value of the five trials. If the material of the unknown 
resistance wire is known, measure its length and diameter (micrometer screw 
gauge) expressed in feet and mils and, applying the formula on p. 442 of "Modern 
Physics, " calculate the resistance in ohms. Compare this value with the method 
of your experiment. Which do you consider the more accurate? 



41 

EXPERIMENT 15 

The Wheatstone Bridge 

Object: To determine the resistance of a conductor by the method of Wheat- 
stone's Bridge. 

Reference: "Modern Physics," Section 619. Study Fig. 683, p. 492, for 
the method of connecting the apparatus. 

Apparatus: A slide-wire Wheatstone bridge, dry cell, D'Arsonval type of 
galvanometer, resistance box, an s.p.s.t. knife switch, connectors and an unknown 
resistance to be determined. 

Procedure: Connect up the apparatus in the manner illustrated in Fig. 
683 of the textbook. Use short lengths of No. 18 wire for the connectors. 
Place the resistor to be determined at X; connect in the adjustable resistance 
box at R. Connect the galvanometer across the points DK, using a short 
wire at D but a piece about 50 cm. long from the galvanometer to K. Connect 
the dry cell across the ends of the German silver wire AC, inserting a single- 
pole-single-throw switch between the battery and the wire. 

Note: This is not shown in Fig. 683, but it is advisable so that the 
battery circuit can be opened when readings are not being taken, thus avoid- 
ing wastage and overheating of the resistance wires. 

Slide the contact key to the 50 cm. mark and remove the 100-ohm plug 
from the resistance box. This introduces a resistance of 100 ohms at R. Now 
press down the key K and observe the needle of the galvanometer. Note: 
Make sure the galvanometer needle is able to turn freely and that the coil to 
which it is attached does not touch at any point as it swings. The reading 
should be zero when no current is passing through the galvanometer. The 
needle will probably jump violently when the key K is depressed. Adjust 
the resistances in the box R, either more or less until the motion of the needle 
is no longer violent and it moves over a few degrees of the scale. 

Note: The plugs in the resistance box should be pressed in firmly to make 
good contact each time they are replaced. 

To make the final adjustment so that the bridge is " balanced" and the 
galvanometer registers zero deflection, move the sliding key K to right or left 
as may be required until, on depressing the key, the galvanometer registers 
zero. 

Read the value of the resistances in the resistance box and the exact position 
of the key K to the nearest millimetre at the point where it touches the wire. 
Record these. 

Results: Tabulate the data and, using the method explained on p. 492 
of the textbook, work out the value of the unknown resistor X in ohms. 

Knowing the dimensions of the resistor, i.e. its length in feet and its dia- 
meter in mils, determine the value of K in the formula for resistance, 

Kl. 

Compare this value with the accepted value for the material of the resistor 
as given in Table 15, Appendix B, of the textbook. 



42 

EXPERIMENT 16 

The Hydrogen Voltameter 

Object: To determine current strength by the use of the hydrogen volta- 
meter. 

Reference: " Modern Physics," Sections 580-582; also Section 586. See 
also " Elements of Physics," by Merchant and Chant, Sections 530 and 531. 

Note the formula, I = — — , where I is the current strength, m is the mass 
t Xg 

of hydrogen liberated, t is the time in seconds and e is the electrochemical 
equivalent for hydrogen. Take the value for e as 0.0000104 gm. per coulomb. 

Apparatus: Hoffman's electrolysis apparatus, 6-volt storage battery or 
transformer-rectifier which will deliver 6-8 volts D.C. when connected to a 
110-volt power line, ammeter (low range), thermometer, barometer, knife switch 
(s.p.s.t.), watch, dilute sulfuric acid (1 to 20), platinum electrodes, connecting 
wires of No. 18 gauge copper. 

Procedure: Set up the Hoffman's electrolysis apparatus with the platinum 
electrodes in place and a thermometer (Centigrade) attached to one arm of the 
H-tube by means of rubber bands. Fill the apparatus with dilute sulfuric 
acid and remove any that spills over, making sure the thermometer is dry and 
that the acid fills both arms of the tube to the top and stands somewhat higher 
in the centre tube. Connect the electrodes in series with the knife switch, 
the ammeter and the 6-volt D.C. current source, making sure that the electrode 
in the tube having the thermometer attached is connected to the negative pole 
of the battery. This electrode will then be the cathode and hydrogen will 
collect in this tube. Close the knife switch momentarily to make sure that 
the apparatus is working and that a steady stream of gas rises from each electrode. 
If necessary, remove any gas that has collected by opening the stopcocks at 
the top but do not spill any acid. Note: Two hands should be used in turning 
a stopcock so that a slight pressure may be maintained while turning, thus 
avoiding leakage. 

Close the switch, observe the exact time in minutes and seconds and allow 
the electrolysis to proceed for several minutes until about 30 cc. of hydrogen 
has collected in the tube. Read the ammeter at intervals of two minutes and 
record. Now open the switch observing the time accurately again. Read the 
thermometer and record. When all the gas bubbles have ceased to rise, read 
the volume of hydrogen to the nearest tenth of a cc. Obtain a reading of the 
barometer so as to give the actual atmospheric pressure in millimetres of mer- 
cury. Measure in millimetres the height, h, of the column of acid in the centre 
tube above the acid in the hydrogen tube. Record this height. The hydrogen 
gas may be released and tested with a match and the oxygen tested with a 
glowing splinter. 

Note : Make sure that no acid runs down over the apparatus and that there 
is no leakage. If any drops of acid have fallen, wash with copious water and 
leave clean and dry. 

Results: Tabulate all data and make the following calculations: 

From Table 9, Appendix B, of the textbook determine the vapor pressure 
of water in millimetres of mercury at the temperature of the experiment. Let 
it be Pw. 

Determine the pressure exerted by the column of acid in the centre tube, 

Pa, thus : Pa = 10 ' mm. (1.1= density of acid) . 
lo.o 



43 

Determine the pressure exerted by the hydrogen, Ph (when dry) thus: 
Ph = P+Pa — Pw, where P is the barometric reading in millimetres of mercury. 

Determine the volume of hydrogen collected at N.T.P. by use of the formula, 
PiV 1= P a V2 
Tx T 2 
where Vi is the required volume at a pressure P x =760 mm., and a temperature 
T l = 273°K and V 2 is the observed volume, P 2 = Ph and T 2 is the observed tempera- 
ture of the experiment expressed in absolute degrees. 

Now determine the mass of the hydrogen collected thus: 

m = — * ' — '-- gm. (1 litre of Hydrogen weighs 0.089 gm.) 

Now substitute in the formula, 1=——, where I is the current in amperes, 

t /\ e 

m is the mass of hydrogen collected, t is the time in seconds and eis 0.0000104. 

Assuming the value of I determined by this experiment to be the correct 
value, determine the percentage error of the ammeter reading as obtained from 
the average value of the observations of the ammeter dur ng the experiment. 

EXPERIMENT 17 

Internal Resistance of Cells 

Object: To determine the internal resistance of a cell (a) by Ohm's law 
method, (b) by the reduced deflection method. 

Reference: " Modern Physics," Section 556. 

Apparatus: A Daniell or gravity cell, voltmeter and ammeter, both grad- 
uated in tenths, knife-switch, resistance box, dry cell. 

Procedure: Connect the gravity of Daniel cell in series with a switch, 
ammeter and resistance box. Connect a voltmeter across the terminals of the 
cell. See Fig. 605, p. 442 of textbook. 

With the switch open read the voltmeter. Record this reading as E volts. 

Since this cell has a high internal resistance, it is not necessary to put any 
other resistance in the external circuit. The resistance box may therefore be 
set at zero and the -witch closed. Read the voltmeter and ammeter. Record 
the ammeter reading (I), and the voltmeter reading (Ei). 

Calculate the resistance of the cell by applying Ohm's law as follows: 

Repeat the experiment with the dry cell in place ol the Daniell cell. In 
this case a small resistance must be introduced in the resistance box before closing 
the switch. 

Note: The current from a dry cell is too heavy to be put through the 
ammeter without some resistance in the circuit. Do not burn out your 
ammeter. Have your teacher check your apparatus before proceeding. 

(b) Reduced deflection method. Connect the Daniell cell, switch, 
ammeter and the resistance box in series. With a zero resistance in the re- 
sistance box, close the switch and take the ammeter reading. Record this. 
Now remove plugs from the resistance box until enough resistance has been intro- 
duced to reduce the ammeter reading to exactly one-half. Record the resist- 
ance of the resistance box. This is a measure of the internal resistance of the 
cell. 



44 



Repeat the experiment using the dry cell, only in this case connect a low 
resistance shunt across the terminals of the ammeter. Remember your am- 
meter is a valuable instrument. Protect it from an overload. 

Results: Tabulate all results as follows: 



Type of 
cell used 


E 


Ei 


I 


Ext. Res. 
R 


Int. Res. 
r 















Compare the results as given by the two methods. Which is more accurate? 
Give reasons. 



EXPERIMENT 18 

Magnetic Field about a Conductor 

Object: To perform Oersted's experiment and to study the nature of the 
magnetic field about a wire carrying a current. 

Reference: " Modern Physics," Sections 561-564. 

Apparatus: A galvanoscope having one turn, several turns and many 
turns, each with their respective binding posts, Pietenpol connectors, 2 dry 
cells or storage battery, Daniell cell, knife switch, four small compasses, one 
large demonstration compass needle, sheet of stiff cardboard 1 ft. square, length 
of bare No. 12 or No. 14 copper wire. 

Procedure: (a) Test Oersted's experiment as illustrated in Fig. 611 and 
Fig. 612, using the Daniell cell and a demonstration compass needle. Test the 
right-hand rule for determining the direction of the current. Place the wire 
above and below the needle and reverse the connections on the Daniell cell, 
testing the rule each time. 

(b) Place the galvanoscope on the bench so that the single wire is parallel 
to the compass needle as it points towards the magnetic North pole. Turn 
the compass so as to bring the zero point directly below the N-pole. Connect 
the Daniell cell with the knife switch in series with the terminals of the single 
galvanoscope wire so that when the switch is closed the current will flow from 
South to North over the needle. 

Close the switch and note the direction in which the N-pole is deflected 
and the number of degrees on the compass scale. Reverse the connections of 
the Daniell cell so that the current flows from North to South. Close the 
switch and read the number of degrees of the angle of deflection. Record these 
readings. Without changing the position of the galvanoscope on the bench, 
repeat the experiment with the compass needle under the few turns of wire. 
Record the angle of deflection for both directions of the current flow. 

Repeat again with the many turns of wire. Record the angle of deflection 
of the needle. 

(c) Pass the heavy copper wire through a hole in the sheet of cardboard, 
supporting the latter in a horizontal position by means of a wooden clamp. 
Note: An iron retort stand is frequently magnetized and may give erroneous 
results. 



45 

Connect the ends of the copper wire to two dry cells or a storage battery 
and the knife switch in series using No. 18 wire. Place the four small compass 
needles around the wire in the manner illustrated in Fig. 613 of the textbook. 

Close the switch and observe the position of the compass needles. Reverse 
the connections so that the current flows in the opposite direction, close the 
switch and again observe the position of the needles. Apply Right-hand Rule 
No. 2 on p. 452 for both tests. 

Results: Tabulate the results of experiment (b) and state the effect ot 
increasing the number of turns of wire. 

Draw diagrams to illustrate the positions of the compass needles in experi- 
ment (c): (i) when there is no current, (ii) when the current flows upward, 
(hi) when the current flows downward. 



EXPERIMENT 19 

Efficiency of Lamps 

Object: To determine the efficiency of various lamps and to compare 
series and parallel wiring for lamps. 

Reference: " Modern Physics," Sections 599 and 600. 

Apparatus: A.C. voltmeter, 0-150; A.C. ammeter, 0-10; 3 40-watt lamps, 
1 25-watt, 1 60-watt, 1 100-watt lamp; 16-c.p. and 32-c.p. lamps; a lamp board 
to be constructed as follows: On a piece of 3-ply wood, 6'' x 3', set out three 
lamp sockets about 8" apart and towards one end of the board. Screw them 
to the board and connect them, in parallel (Fig. 654), with a heavy insulated 
electrician's wire. Remove only enough of the insulation to make good contact 
on the sockets. Spread the rest of the wire along the board and fasten the 
ends to two terminal binding posts, well insulated, at the extreme end of the 
board. On one wire insert a lamp socket to take a fuse plug and a single-pole- 
single-throw porcelain based knife switch. Cut the wire at two points equally spaced 
between the terminal post and the first lamp socket, and insert the fuse socket 
and the knife switch in series with each other. On the other wire insert another 
lamp socket to take a second fuse plug and two binding posts for attaching 
an ammeter. You should now have in series going from one binding post to 
the other, a lamp socket (A), a knife switch, a group of three lamps (B, C and 
D) in parallel, two binding posts (M and N), and another lamp socket (E). 

Procedure: (a) Connect the terminals of the lamp board to an A.C. 110- 
volt outlet by means of a lamp cord and plug. Insert two 6-ampere fuse plugs 
in sockets A and E. These are to protect the measuring instruments. 

Place a 25-watt lamp in socket B. Connect an ammeter across M and N 
and a voltmeter across the terminals of the lamp B. Close the switch and read 
the ammeter and voltmeter. Record the readings in a table as shown below. 

Do the same for the 40-watt, the 60-watt, the 100-watt, the 16-c.p. carbon 
and the 32-c.p. carbon lamps. 

Record all readings. Note: Open the knife switch each time you replace 
a lamp in socket B. 

(b) Place a 40-watt lamp in B. Take readings and record. 

Place another 40-watt lamp of the same make in C. 

Close the switch and read the ammeter and voltmeter. 



46 

Open the switch and transfer the voltmeter to the terminals of lamp C. 
Record readings. 

Insert a third identical 40-watt lamp in socket D. Close the switch and 
read the ammeter and voltmeter, changing the latter to D after checking to 
see if there is any change in the reading at C. Record all readings. 

(c) Remove the fuse plug nearest to the ammeter and insert a 40-watt 
lamp in its socket (E). Remove lamps from C and D. You now have lamps 
in B and E in series. Close the switch and determine the ammeter reading 
and the voltage across each lamp separately and across the two together. Record 
all readings. 

Results: Tabulate the data of experiment (a) as follows, taking a 25-watt 
lamp to have a 20 c.p., a 40-watt lamp to have a 32 c.p., a 60-watt lamp to 
have a 50 c.p. and a 100-watt lamp to have 100 c.p.: 



Kind of 
Lamp 


Volts 


Amps 


Watts 
Used 


Rated 
wattage 


Candle 
Power 


Watts 

per 
candle 


Cost per 
candle 
per hour 



















Cost of electricity to be reckoned at 10c per kilowatt-hour. 
Tabulate the results of experiments (b) and (c) thus: 



No. of lamps 


Connection 


Voltage 


Amperage 


Single 
Two 
Three 
Two 


Parallel 
Parallel 
Series 







What are the advantages of parallel wiring for lamps over series wiring? 



EXPERIMENT 20 

The Electric Motor 

Object: To study the action of a simple electric motor. 

Reference: " Modern Physics," Sections 635-640. 

Apparatus: St. Louis type demonstration motor, dry cell. 

Procedure: Remove the bar magnets from their holders and connect the 
dry cell to the armature terminals. Turn the armature by hand through a 
complete circle and test the polarity of each end of the armature by means of a 
barj magnet (law of magnetic poles) at several points in the circle. Note the 
change in polarity as the two segments of the commutator move from one brush 
to the other. Draw diagrams as in Figs. 708-710, p. 508 of textbook, and 
indicate the polarity in different positions. 

Now insert the bar magnets so that a N-pole of one and a S-pole of the 
other are close to the armature. Connect the dry cell as before and set the 
armature rotating. 



47 

Study the effect of separating the magnets further apart on the speed of 
the motor, and the effect of using two like poles. Reverse the connections of 
the dry cell. Note the direction of rotation of the motor. Now disconnect 
the dry cell, remove the bar magnets and insert the electro magnet. Connect 
the dry cell, the armature terminals and the field magnet all in series. Note 
the direction of rotation of the armature. Change the connections on the dry 
cell so as to reverse the direction of the current. Note the direction of rotation 
now. Is there any change. Wiry is this different from the effect with per- 
manent field magnets? 

Now connect the armature, the field magnet and the dry cell in parallel. 
Again try the effect of changing the connections on the dry cell so as to reverse 
the direction of the current. How does this affect the direction of rotation of 
the motor? 

Results: Draw diagrams to show the connections,' the direction of current 
flow and direction of rotation, also polarity of the field magnets for each of the 
three types used, i.e., (i) using permanent field magnets, (ii) series wound motor, 
(iii) shunt wound motor. 



BIOLOGY 2 



The following exercises are designed to aid the student of Biology in carry- 
ing out a number of individual experiments. It is not expected that all those 
listed should be completed, but an effort should be made to perform as many 
as possible. Nor is it intended that they should replace those outlined in the 
textbook. Many of these, also, should be performed by the student. Students 
should be encouraged to learn much of their Biology from actual observations, 
rather than by merely reading the textbook. 

Many of the details of the experiments may be modified to suit the local 
conditions. 

Blueprints make accurate and permanent records of many experiments. 

The teacher should write for "Turtox Leaflets," supplied free by the 
General Biological Supply House, Chicago. These give very helpful instructions 
on such items as " Mounting Insects," " Making an Aquarium," "The Feeding 
of Minute Animal Organisms," etc. The catalogue of this Supply House is 
most helpful to teachers of Biology, and may be obtained upon request. 



1. USE OF THE MICROSCOPE 

1. Learn names of the parts of the instrument; e.g., stage, aperture, 
diaphragm, mirror objective, eyepiece, etc. There should be screws for coarse 
and for fine adjustment. Mirror should have plane and concave sides. 

2. Preparation of object for viewing: 

The object must be transparent, a very thin section of plant or animal 
tissue, or protozoans, aphids, water fleas, moulds, algae, etc. 

Place the object on a clean glass slide; place a drop of clean water on it 
(dry specimens do not transmit light efficiently), cover with a cover glass. 

3. Place the specimen prepared as above on the stage, and centre it over 
the aperture. 

4. Turn the mirror below the stage toward the source of light. If the 
light comes from a window, use the plane side of mirror; if from a lamp flame or 
filament, use the concave side. 



48 

Tilt the mirror until you see the beam of light pass through the glass slide 
and specimen. 

5. See that the low-powered objective is in place above the specimen. 
With your eye on the level of the stage, turn the objective down until it almost 
touches the cover-glass. (Never turn screws to lower objective, with your 
eye to the eyepiece, unless the specimen is plainly in view.) 

6. Now place your eye above the eyepiece. Light should be coming 
through to your eye. Turn the screws to raise the objective. Continue until 
image of specimen comes into view. 

7. Now that you have the specimen in view, several improvements may be 
made. Experiment with mirror and with diaphragm until you have the best 
possible light arrangement. With eye still placed to the eyepiece, take the 
slide on which specimen is placed in both hands and move it gently back and 
forth to view different parts of specimen. 

8. If you desire a higher magnification, there are several methods you may 
adopt. You may replace the eyepiece with one of higher power. You may 
raise the eyepiece by lengthening the tube between objective and eyepiece and 
then re-adjusting the focus. Or you may replace the objective with one of 
higher power. For the high power objective you will need more light. 



2. THE AQUARIUM 

Every biology classroom should have an aquarium. Complete instructions 
on making one will be found in " Everyday Biology," pages 636-8. Water 
weeds may be anchored to the bottom by tying a glass stopper or a piece of 
glass tubing to the lower end of the plant. Roots should soon strike into the 
sand. In addition to fish, snails should be present. If the aquarium is a large 
one, salamanders may also be stocked. However, these have a tendency to 
attack the fish, and so are better kept by themselves. If it is desired to hatch 
frog tadpoles from eggs, or young snails from eggs, the fish must be removed. 
If the water becomes murky, it probably indicates the presence of too many 
animals. 

THE TERRARIUM 

" Everyday Biology" also gives directions for the making of a terrarium 
(page 645). A desert terrarium, including a few cacti and " horned toads, " 
makes a very interesting display. " Horned toads" (lizards) maybe obtained 
from the Biological Supply House, Chicago. 



3. MICROSCOPIC ORGANISMS 

(For all students) 

Materials: Small quantity of organic matter: a handful of grass, dry hay, 
dead leaves, slices of carrot, etc. 

Procedure: Place any of the above in a jar of water and leave in a warm 
place, 70-90 degrees Fahrenheit, for several days. 

Take a clean glass slide. Place upon it a drop of clean water. Pluck a 
few threads from an old piece of clean cotton and pick them apart with a needle 
until the fibres are very finely divided. Place these in the drop of water on the 
slide. These fibres form a trap which restricts the movements of the protozoa 
and allows the observer to keep them in view. 



49 

Now take a sample of the infusion from the jar and place a drop of it among 
the wet fibres. Cover with thin glass. Examine with the low power objective 
of the compound microscope. There are certain to be paramecia and other 
ciliata, and you may be fortunate enough, if your infusion was made with decay- 
ing leaves, to find amoebae. The latter are more likely to be found at the 
bottom of the jar. 

Water from Sloughs and Ponds — 

Samples should be collected from as many of these sources as possible. 
If there is a green scum on the water there are sure to be algae, such as closterium. 
ulothrix, spirogyra. 

On the edges of leaves under water, the protozoan, Vorticella, is usually 
found. Place the wet leaf on a slide and bring the edge of leaf into sharp focus 
with the low power of microscope.. Then move the slide carefully, keeping 
the edge always in view. 

Vorticella may be recognized by its bell-shaped body, the ring of waving 
cilia around the mouth, and by the long coiling thread which attaches it to the 
leaf. Larger organisms, rotifers, cy clops, daphne, etc., visible to the naked 
eye, may also be found in pond water. These make suitable specimens for 
microscopic studies. 

Soft jelly-like masses may often be found on decaying wood in pond water. 
These are fresh sponges. Some ponds contain hydra, usually found on the 
stems of bullrushes under the surface of the water. 



4. BACTERIA 

(For several students) 

Bacteria are minute fungus plants that are either parasites or saprophytes. 
They are widely distributed and can be grown on artificially prepared media. 

Materials: Beaker 400 cc; test tubes; funnel; flask; cotton wool; Petri 
dishes; burner; water; agar-agar; beef extract; a piece of cotton. 

Procedure: Into the beaker containing about 200 cc. of distilled water, 
put 3 grams of agar-agar and about 1 gram of beef extract. Dissolve the agar- 
agar by heating the water. Strain through cotton into a flask and heat again. 

Sterilize the Petri dishes and test tubes by boiling in water for 5 minutes. 
Pour the sterile medium into the Petri dishes or half fill the test tubes. Cover 
the dishes and plug the test tubes with cotton wool. Rest the test tubes at an 
angle to form a larger surface. Allow the liquid to stand till cool and firm. 

Set one test tube aside as a control. 

Remove the cotton wool from a test tube or the cover from a dish and 
expose contents to the room air for ten minutes. Cover as before and label. 
Similarly expose other culture media to (1) a drop of dirty water, (2) a drop of 
milk, (3) dust from the desk, (4) your finger. Cover and label. The dishes 
containing the drops of liquid should be shaken to spread the liquid. Set the 
dishes in a warm dark place. 

Examine after several days. Note the number of colonies, color, shapt\ 
rate of growth. Record your observations. When a culture is sufficiently 
developed make an accurate record in the form of a drawing. 



50 

5. MOULDS 

(For several students) 

Materials: Saucer; large beaker; piece of bread. 

Procedure: Moisten a piece of bread. Either leave it exposed for several 
hours, or spinkle with dust from two or three sources. The bread may be dusted 
with other mould spores, if available. Cover the bread with the beaker, and 
set aside in a warm place. Examine daily. When growth begins, examine 
closely with a magnifying glass, and under the microscope. 

Record your observations with diagrams. 

Several kinds of moulds may be found. 

If you have been successful in obtaining the " black mould," place a black 
sporangium (see page 125 in textbook) on a glass slide. On it place a cover 
slide and press gently so as to crush the sporangium. Now examine under the 
microscope, first low, then high power. 

Additional Experiment on Moulds 

(For all students) 

Materials: Test tubes; cotton wool; clear fruit juice. 

Procedure: Put a few cc. of fruit juice into 2 or 3 test tubes. Add an 
equal volume of water. Shake. Inoculate the liquid by adding a little mould 
to it, or by sprinkling it with dust. Plug the test tubes with cotton wool, 
and set in a warm place. 

Observe as above and record your observations. 

6. DISSECTION OF EARTHWORM 

(For pairs of students) 

Materials: Dissecting pan, forceps, scissors, dissecting needles, pins. 
Dissect under water, renewing water frequently. 

1. Lay the specimen on board, dorsal side uppermost: stretch and pin at 
ends, slanting pins away from the worm. Make an incision through the skin 
near the posterior end and to one side of the dorsal blood vessel. With scissors 
cut forward along a line parallel to the intestine until the anterior end is reached. 
With forceps, lift the cut edge of the body wall and run a dissecting needle along 
the side of the intestine to cut the partitions that extend from intestine to body 
wall. Turn the edges of the body wall back and pin them down, slanting the 
pins so that they are out of the way. 

2. The intestine is the most prominent organ disclosed. It is dark-colored 
from its contents and nearly fills the body cavity. 

3. Along the top of the intestine is the dorsal blood vessel. 

4. With a lens, observe the partitions. How do they correspond to the 
segments you have observed in the external surface? 

5. In the first six segments (anterior end) you will find more muscle tissue 
than in the remainder of the body. These are attached to the pharynx. 

6. On the dorsal side of the second segment you should see two ganglia, 
white masses of nerve tissue which serve as a brain. From these, a nerve cord 



51 

passes on either side of the pharynx to rejoin in a thin white thread which 
extends the entire length of the ventral side. You may be able to see it with 
a lens. 

7. In the region of the tenth segment are the sperm sacs, several pairs of 
white bodies, plainly visible. 

8. Lying in segments eight to twelve are the aortic arches. These serve 
as hearts to pump the blood. They can be traced from the dorsal blood vessel 
to the ventral blood vessel. The aortic arches may be seen best by anesthet- 
izing a living worm (chloroform or ether), and holding it up by the extreme poster- 
ior end, swinging it around several times until the centrifugal force causes 
the blood to collect in the anterior end. If it is then opened, the aortic arches 
will be found distended with blood. 

9. When the sperm sacs are removed, you may find in the ninth and tenth 
segments two small pairs of white spherical bodies, the sperm receptacles or 
spermathecae. 

10. The ovaries may be found in the thirteenth segment. 

11. Trace the alimentary canal. The mouth occupies segments one and 
two; the pharynx, four to five; the oesophagus, six to fourteen; the crop, 
fifteen to sixteen; the gizzard, seventeen to eighteen. The intestine occupies 
the remaining segments. 

12. Remove the intestine, noting the ventral blood vessel and nerve cord. 

13. Attached to the ventral side of each segment is a pair of tubes thrown 
into many loops. These are the nephridia or kidneys. 

14. Examine the body wall under a lens and later with microscope. The 
outer layer peels off easily and is very thin. This is the cuticle. The next 
layer is composed of circular muscles, and the third, of longitudinal muscles. 

15. Mount a drop of liquid found in the body cavity under the microscope. 
The white corpuscles are clearly seen. 



7. THE GRASSHOPPER 

(For all students) 

Materials: Grasshopper; dissecting needle, or large pin; forceps; magnifier; 
white paper. 

Procedure : Examine the general structure of the insect, using the magnifier 
as an aid. Note the three distinct body divisions. Name these. Draw the 
grasshopper (side view) and label the main features. 

Head — Examine the head with the glass. Locate the following parts — 
feelers, compound eyes, simple eyes (ocelli), mouth, palps. With the aid of the 
forceps, carefully remove the mouth parts and arrange them on a sheet of paper 
in their relative positions — -upper lip, lower lip, mandibles (hard, black jaws). 
maxillae (bearing palps), tongue. 

Make a diagram of the mouth parts as arranged. Label each part. (Dia- 
grams of mouth parts may frequently be found in reference texts.) 

Thorax — Note the shape of the thorax and its three segments (prothorax. 
mesothorax, metathorax) . Note the number of wings, their structure and 
shape. To what segments of the thorax are they attached? Compare the 
under wing and the top wing. 



52 

Examine the legs and note their insertion on the thorax. Hunt up in a 
reference text the names of the different segments of the leg. 

Abdomen — Count the number of segments. Locate the spiracles and 
count them. The ear of the grasshopper can be easily seen on the front segment 
of the abdomen above the insertion of the large jumping leg. The end of the 
abdomen of the female is modified into an ovipositor or egg layer. 

Using a sharp knife or razor blade, slice a thin section of the compound 
eye and examine under the microscope. 

A cabbage butterfly may be examined if desired. A piece of a wing should 
be examined under the microscope to observe the scaly covering. This will 
be more easily observed if some of the scales have first been removed by rubbing 
the wing with the finger. 

8. INSECT LIFE HISTORIES 

(Class project) 

Materials: Flower pots; lamp chimneys; cheesecloth; rubber bands; soil; 
plants or twigs for insect food. 

Procedure: Collect insect eggs or larvae. Note the kind of plant upon 
which each is found in order to supply the proper food. Fill the pot with soil. 
Close the top end of the chimney with cheesecloth held with the rubber band. 
Place a young plant or twig in the soil. Add water. Put the eggs or larvae 
on the plant and set the chimney over the plant. 

Make daily records of any changes which occur. 

The development of mosquitos from eggs can be readily watched by placing 
the eggs in a beaker of rain water (or slough water), setting the beaker on the 
soil and covering with the chimney. 

Permanent Life History Exhibits 

Suggested exhibits to be made by different groups of students are: Grass- 
hopper, monarch butterfly, honey bee, potato beetle, cutworm, dragonfly, house- 
fly, promethia moth, red underwing moth (catocala). 

Cocoons containing living pupae of the large silk moths may be obtained 
from the General Biological Supply House, Chicago. When hatched, excellent 
exhibits of these may be made, showing the cocoon (outside and inside), pupal 
case (in cocoon) and adults (male and female). 

Materials: Riker mounts (or cigar boxes, cotton batting and cellophane); 
small wide-mouthed vials; alcohol; specimens. 

Procedure: Place a few eggs of the cabbage butterfly (the common white), 
obtained from the leaves of the cabbage in early summer, in a vial. Add alcohol 
and stopper tightly. Later place one good sized larva in a second bottle. Add 
alcohol and stopper. Repeat later with a pupa in a third bottle. Mount a 
specimen of the adult butterfly with wings spread. Do not use a pin in the 
thorax. The body may be held firmly in position in the groove of the mounting 
board by placing pins against the body behind the wings. 

Spread a layer of cotton batting in the cigar box, sufficient to fill the box. 
Place the bottles and the adult insect in position on the batting. Identify each 
by a typewritten label. At the bottom of the exhibit place another label on 
which are shown the names (scientific and common), date collected, etc. Paste 



53 

the sheet of cellophane over the box. The sheet should press lightly on the 
specimens. Riker mounts are more satisfactory than cigar boxes, but also 
more expensive. 

9. CLASSIFICATION OF INSECTS 

(For all students) 

Materials: Several specimens of insects, including some of the following: 
House fly, grasshopper, moth or butterfly, bee, dragonfly, potato beetle, stink 
bug, mosquito. 

Using the following key, classify each specimen: 

Key 

Order 

With two wings only... Diptera 

With four wings — 

Outer pair of wings hard and shell-like Coleoptera 

Outer wings with the front half hard and the rear half 

membranous Hemiptera 

Wings much alike — 

Both pairs of wings colored; covered with scales ...Lepidoptera 

Wings thin and transparent — 

Outer wrings folded over inner fan-like wings; 

held close along body when at rest. ...Orthoptera 

Wings held at right angles to the body — 

Mouth parts for sucking and chewing Hymenoptera 

Mouth parts for chewing ..Odonata 

In your note book (1) copy the "key", (2) write down the Orders listed 
in the key with the name of insects classified in each Order. 

♦ 

10. DISSECTION OF FROG 

(For small groups of students) 

Materials: Frog; dissecting board; pan; dissecting needle; scissors; knife; 
forceps; pins; probing rod. 

Procedure : 

1. If the frog is living, place it in a wide-mouthed jar. Pour ether or 
chloroform on a piece of absorbent cotton and drop the cotton in the jar. Seal 
and leave for half an hour. 

2. Place the frog on its back on a dissecting board. Stretch the forelegs 
well forward and tack them to the board. Stretch the hind legs well back and 
tack them. With forceps pinch up a fold of skin near the pelvis. With scissors, 
snip through the skin and slit the skin from pelvis to chin. Loosen the skin 
wherever it adheres to the underlying tissues and turn it back. 

Cut outward from the centre line to each leg and slit part way along the 
leg. Pin the skin back so that it is out of the way. 

Cut through the muscular wall of the abdomen and carry the cut forward 
in the same way as with the skin. Be careful to keep this cut a little to one 
side of the centre line and watch the point of the scissors to see that no internal 
organs are injured. Tack the flaps of the abdominal wall. 

3. The most prominent organs in the body cavity are the liver, and, if 
the frog is a female, the oviducts. It may be necessary to lift or remove these 



54 

to see the other organs. The liver is chocolate-colored and has several lobes. 
If the oviducts are filled with eggs they will appear black, owing to the color of 
the eggs; if not, then they appear as long white tubes. They must not be con- 
fused with the intestine. 

4. At the anterior edge of the liver and between the lobes is the reddish 
heart. It is enclosed in a very thin transparent sac, the pericardium. Pinch 
this up with the forceps, cut through it and remove most of it. If the frog is 
freshly-killed, the heart may be still beating. The main artery from the ventricle 
divides into two branches, right and left, and each of these into three sub- 
divisions: 1, to the head, the carotid; 2, to the body, the aorta; 3, to the lungs 
and skin, the pulmo-cutaneous. 

You may puncture the heart and probe with a blunt wire to trace the 
arteries and veins. Later, if you wish, you may dissect the heart. 

5. On either side of the heart and partly hidden by the liver are the two 
lungs. If they are collapsed, they may be inflated with a glass tube or blow- 
pipe applied to the glottis. Compare them with lungs of a bird or mammal. 

6. Push the liver aside to expose the stomach. Probe from the mouth 
through oesophagus to stomach with a blunt rod. 

7. At the posterior end of the stomach is the intestine. Trace it through- 
out its course. How does it compare in number of folds with: a fish? a duck? 
a chicken? or a rabbit? 

8. Notice the thin membrane which stretches from fold to fold of the 
intestine. This is the mesentery. Where is it attached to the body wall? 
Notice the blood vessels which form a network in the membrane. Where are 
the capillaries which connect arteries and veins? 

9. The pancreas lies in the first fold of the intestine and the stomach. It 
has the appearance of a yellow cord with lateral branches. 

10. The intestine empties into an organ called the cloaca. This receptacle 
receives the wastes from the intestine, the urinary bladder, and also the sperms 
or eggs from the reproductive organs. 

11. On the dorsal side of the body cavity and on either side of the cloaca 
is a flattened, reddish body, the kidney. 

12. Near the ventral surface of each kidney is the spermary or ovary, 
depending upon the sex of the frog. Sperm ducts or oviducts lead from these 
to the cloaca. 

13. The speen is a small red spherical body close to the left kidney. 

14. The thyroid glands may be found on either side of the oesophagus 
near the pharynx. 

11. CORPUSCLES OF FROG OR FISH 

A live frog is enclosed in a small cloth bag with a drawstring tightened 
around the hind leg so that only the foot protrudes. 

The bag may be secured with strings to the stage of the microscope so 
that the webbing of the extended foot is over the aperture and under the low 
power objective. 

The webbing of the foot is sufficiently transparant to enable the student 
to watch the corpuscles flowing through the veins and capillaries. 



55 

An even better view of corpuscles, coursing through blood tissues, may be 
seen in the tail of a goldfish or minnow. Wrap the live fish in a clean wet cloth 
with only the tail protruding. Place the tail on a wet glass slide and view under 
the low power of the microscope. 

Tadpoles may also be used for this purpose, if they are caught in the stage 
when they are breathing by external gills. The circulatory system where it 
passes through the gills may easily be seen. The tiny tadople can be placed 
on the glass slide with its gills in contact with the glass. 

12. GERMINATION OF FERN SPORES 

(For two or three students) 

Materials: Culture dish or saucer; small unglazed plant pot, 3"; large 
beaker; moss (sphagnum moss, if available); fern spores; water. 

Procedure: Fill the pot with the moss or some suitable substitute. Wet 
moss and pot thoroughly. Invert the pot with moss and place on the bottom 
of a Petri dish or in the saucer. Dust the fern spores (from sporangia) liberally 
over the damp pot. Add a little water to the dish and cover with a large beaker. 
Set aside at room temperature. These spores may take weeks to germinate. 

Examine from time to time and when germination begins, as seen by the 
green color, remove a few prothallia to a glass slide. Add a drop of water and 
cover with a cover slip. Examine under the low power of a microscope. 

Make a cross section diagram of the apparatus and label. Draw several 
successive stages in the germination as seen under the microscope. 

13. STRUCTURE OF MONOCOTYLEDONS AND 
DICOTYLEDONS 

(For all students) 

Materials: Young stems of plants; geranium, fuchsia, lilac, maple, etc.; 
ink or dye; razor blade; magnifier; microscope. 

Procedure: (1) Stems: Dicotyledons. Make thin slices of stem of 
geranium, fuchsia, etc., and examine them under the low power of the micro- 
scope. Cut stems of the same plants and of lilac, willow, maple, etc., with 
vigorous leaf systems. Place the cut ends in a jar of dye (eosin, weak solution 
of red ink, etc.). Leave for one or two days. Remove and slice thin cross 
sections. 

Notice the tissues that have carried the dye. How are they arranged? 
(The wood cells, xylem, carry liquids upward in the stem.) 

Examine the slices with a hand lens and with a microscope. Notice the 
epidermis, the cortex, bast, wood, and pith. The wood should show the stains 
from the dye. The bast should be uncoloured, but should be in the same 
bundle with the wood and toward the outer edge of the stem. Cells of pith 
and cortex are much larger than wood and bast cells, the pith in centre of stem, 
and extending outward between bundles of wood. The cortex lies outside of 
the bast and extends inward between the bundles. The cambium layer is not 
a part to be seen as a distinctive type of cell. It is the region of growth, and 
new cells of wood, bast, pith and cortex are being formed there during the 
growing season. When cells are growing most rapidly the walls will be weak, 
and a sharp twist will sometimes separate bast and cortex from wood and pith. 
(Every boy has done this in making willow whistles.) This is a good method 
for locating the cambium layer. 



56 

Stems: Monocotyledons. Repeat the above procedure with stems 
of corn, onions, lilies, cereals, dates. Dye rises in the wood, as before, but the 
coloured tissues will be found in a different pattern. Bast and wood are still 
bound in bundles, but these bundles are scattered in the pith. 

(2) Leaves. Collect and compare leaves of monocotyledons and dicoty- 
ledons. Generally speaking the former are parallel-veined, and the latter, net- 
veined. 

(3) Flowers. Collect and compare flowers of the two classes. Count 
the petals, sepals, stamens, lobes of stigma, sections of ovary, etc. Monocoty- 
ledons generally have these parts in multiples of three, dicotyledons, in multiples 
of four or five. 

(4) Seeds. Collect and soak seeds of flowering plants. Remove the 
testa or outer covering; the origin of the terms " monocotyledon" and " dicoty- 
ledon" should be clear. In dicotyledons, e.g., beans, peanuts, etc., the seeds 
should divide easily into two parts, the cotyledons. 



14. FOOD CONTENTS OF SEEDS 

(For all students) 

Seeds contain one or more of the following food materials— starch, protein, 
fat, oil, mineral matter. 

Instructions for making tests for determining the presence of any of the 
above materials may be found in Exercise No. 15 of the Chemistry experiments. 



15. IDENTIFICATION OF TREES 

(For all students) 

During their study of Biology, students should become familiar with the 
names and appearance of several of the common trees and shrubs of the district. 
The following exercise should be carried out in the early spring, when the buds 
are beginning to expand. 

Materials: Young, vigorous twigs (length 5") of several trees and shrubs: 
poplar, birch, maple, Manitoba maple, ash, elm, lilac, willow, tamarac,j pine; 
magnifier; dissecting needle. 

Procedure : Note carefully the following features : 

(1) Colour and appearance of bark of stem. 

(2) Relative position of buds on stem (opposite one another or alternate). 

(3) Shape and colour of buds. 

Remove one large bud and carefully dissect it, placing the scales and leaves 
on a sheet of paper in order as they are removed from the^bud. Note the 
young stem which remains after all leaves are removed. 

Make a drawing to show these scales and miniature leaves. 

In your notebook, rule a page as shown below, leaving plenty of space for 
the drawings. Under the headings "Twig", "Bud" and "Leaf", make careful 
drawings of these parts. Rule a space for each plant examined. 



57 



Plant 


Twig 


Bud 


Leaf 


Lilac 

















16. SEED STRUCTURE 

(For all students) 

Materials: Bean seeds and corn seeds soaked for 24 hours; magnifier; 
iodine (weak solution). 

Procedure: Bean: On the testa or seed coat, find the hilum or scar where 
the seed was attached to the pod. Near the hilum is a tiny opening, the micro- 
pyle, which admitted the pollen tube to the ovule. Make two drawings of the 
bean, one side view, the other from above, showing the hilum. Label. 

Remove the testa. Note the two cotyledons, held together by the embryo. 
Open the two parts, carefully breaking them apart. Locate the plumule or 
little leaves, and the stem or hypocotyl. Make a drawing and label. 

Corn: Make two drawings of the corn seed — front and side views. Note 
the light coloured area — the embryo. Cut the seed lengthwise through the 
embryo. Stain the cut surface lightly with the iodine and note which part 
contains the starch. Observe the embryo — plumule, hyprocotyl and cotyledon. 
Make a diagram and label. 



17. SEED GERMINATION 

(For several groups of two or three students) 

Materials: Flat wooden boxes; sawdust, sand or soil; bean seeds; pea 
seeds; corn seeds. 

Procedure: Soak all seeds for 24 hours before planting. In the box, plant 
20 to 30 seeds of each kind. Keep the sand moist, but not too wet. Dig up a 
few seeds every other day and record, by labelled drawings, the successive stages 
in the growth of the seedlings. 

This experiment may be varied to suit the size of the class. If desired, a 
number of seeds may be planted at intervals of three days, thus giving, in time, 
a complete series of stages of growth. One class period would then enable the 
students to record the complete series. 

By keeping some boxes in bright light, while others are kept in a weaker 
light, the effect of light upon the growth of the seedlings may be studied. 

In small classes, students (in pairs) may be required to carry out the entire 
experiment. 



58 

Among the factors to be noted are: 

(1) Time required for germination. 

(2) First part of embryo to break through the testa. 

(3) Part to appear first above ground. 

(4) Position of cotyledons in seedlings. 

(5) Rate of growth. 



MUTILATION OF SEEDLINGS AS METHOD OF STUDYING 
FUNCTIONS OF DIFFERENT PARTS 

(For several students) 

In trays, plant rows of seeds. Sawdust is easier to use than soil. When 
germination has taken place and the leaves are beginning to appear above the 
surface of the sawdust, dig up specimens carefully; from one cut off the cotyledons 
or remove the endosperm; from another remove the radical; from another the 
plumule. Replant all parts, labelling them with distinctive numbers or words. 
Continue to water all specimens. Keep a record of their subsequent progress. 
Be sure to leave two or three plants uninjured as a control. 



18. FLORAL STRUCTURE 

(For all students) 

Materials: A few complete flowers, such as lily, radish, petunia, buttercup, 
sweet pea; needle; magnifier; forceps; white paper; knife. 

Procedure: Examine the whole flower, noting the different parts from 
outside and inside. Cut the flower through the middle and make a drawing 
of the parts observed. The base of the flower is known as the recepta^e. On 
this are the sepals composing the calyx. Note their shape, colour, size, number 
and whether they are united or separate. The next envelope is the corolla, 
composed of petals. Examine these as you did the sepals. The stamens consist 
of filaments and anthers. Examine the anthers carefully, cutting them open 
to observe the pollen grains. Examine some pollen under the microscope. 
In the centre of the flower is the pistil. It consists of ovary, style, and stigma. 
Feel the stigma. 

Complete the following table in your notebook. Make drawings under 
the heading "shape." 



59 



Part 


Colour 


Shape 


Composed of 


Function 


Receptacle 










Calyx 










Corolla 










Stamen 










Pistil 











19. GERMINATION OF POLLEN GRAINS 

(For several students) 

Materials: Petri dishes or saucers; sugar; water; pollen grains of several 
kinds of flowers. 

Procedure: In 100 cc. of water dissolve about 1 gram of sugar. Boil for 
a few minutes. When cooled pour a little solution into each of the dishes. 
Dust some pollen grains from the anthers of a flower onto to the solution. Cover 
and set in a warm place till next day. Examine some drops of water under 
the microscope — first low power, then high power. 

Make drawings of your observations. 



20. SNAILS' EGGS 

An interesting study may be made of cleavage of fertilized cells and em- 
bryonic development if a few mature snails are kept in a glass jar in the class- 
room. 



60 

Egg clusters are deposited on the sides of the jar. These may be scraped 
off with, a sharp knife and examined under the microscope. Sperms may some- 
times be detected under the high power objective, swimming in the water surround- 
ing the eggs. 

If taken soon after fertilization takes place, the egg may be seen going 
through the process of cleavage. The one cell may be seen dividing into two, 
the two into four, and so through other successive stages, blastula, gastrula 
until shells are formed and the young snails are ready to emerge from their 
gelatinous envelope to forage for themselves and live their independent lives. 



21. WEEDS OF ALBERTA 

(For all students) 

Materials: Complete specimens of several weeds common to your locality. 
Magnifying glass. 

An herbarium of weeds should be prepared for every biology laboratory. 
These specimens should show as many parts of the plant as possible, and after 
being pressed and dried between large sheets of blotting paper, they should 
be neatly mounted on regular mounting sheets, and accurately labelled. Thick 
roots should have the back sections cut away. Freshly collected weeds are, 
however, preferable for study. 

Coloured charts of Alberta weeds may be obtained from the Department 
of Agriculture, Edmonton. 

Using a full page in your notebook, rule a table, as shown below. Under 
the headings — "Leaf, " " Flower, " "Seed or Fruit," make drawings of these 
parts respectively. Ten or twelve of the noxious weeds in your neighborhood 
should be examined. 



Weed 


Habitat 


Leaf 


Flower 


Seed or fruit 


Character- 
istics 
















































61 

LIST OF APPARATUS AND MATERIALS 

Aquarium 
Beakers, 400 cc. 
Beakers, 250 cc. 
Cellophane sheets 
Cheesecloth 
Chemicals — 

Alcohol 

Ammonia 

Carbondisulphide 

Chloroform 

Eosin dye 

Fehling's solution 

Iodine 

Nitric acid 
Cotton wool 
Cotton batting 

Cover slips (for microscope slides) 
Dissecting board 
Dissecting needles 
Dissecting pan 
Flower pots, 3" 
Flower pots, 4" 
Forceps 

Jars (of various sizes) 
Knife 

Lamp chimneys 
Magnifying glasses 

Microscope (with high power and low power) 
Microscope slides 
Petri dishes 
Pins 
Sand 
Sawdust 
Soil 

Riker mounts 
Wooden flats 
Vials (wide mouth, glass) 



LB 1629-5 A3 A35 1944 GR-10-12 

BULL-B 

PROGRAMME OF STUDIES FOR THE HIGH 

SCHOOL -- 

NL 40031276 CURR HIST 




llll I II III I II I II II 

*0000 32262867* 



DATE DUE SLIP 



































































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